diff --git a/test/functional/test_framework/address.py b/test/functional/test_framework/address.py
index e5d06f039..247c640e8 100644
--- a/test/functional/test_framework/address.py
+++ b/test/functional/test_framework/address.py
@@ -1,66 +1,66 @@
 #!/usr/bin/env python3
 # Copyright (c) 2016 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Encode and decode BASE58, P2PKH and P2SH addresses."""
 
-from .script import hash256, hash160, sha256, CScript, OP_0
+from .script import hash256, hash160, CScript
 from .util import bytes_to_hex_str, hex_str_to_bytes
 
 chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
 
 
 def byte_to_base58(b, version):
     result = ''
     str = bytes_to_hex_str(b)
     str = bytes_to_hex_str(chr(version).encode('latin-1')) + str
     checksum = bytes_to_hex_str(hash256(hex_str_to_bytes(str)))
     str += checksum[:8]
     value = int('0x' + str, 0)
     while value > 0:
         result = chars[value % 58] + result
         value //= 58
     while (str[:2] == '00'):
         result = chars[0] + result
         str = str[2:]
     return result
 
 # TODO: def base58_decode
 
 
 def keyhash_to_p2pkh(hash, main=False):
     assert (len(hash) == 20)
     version = 0 if main else 111
     return byte_to_base58(hash, version)
 
 
 def scripthash_to_p2sh(hash, main=False):
     assert (len(hash) == 20)
     version = 5 if main else 196
     return byte_to_base58(hash, version)
 
 
 def key_to_p2pkh(key, main=False):
     key = check_key(key)
     return keyhash_to_p2pkh(hash160(key), main)
 
 
 def script_to_p2sh(script, main=False):
     script = check_script(script)
     return scripthash_to_p2sh(hash160(script), main)
 
 
 def check_key(key):
     if (type(key) is str):
         key = hex_str_to_bytes(key)  # Assuming this is hex string
     if (type(key) is bytes and (len(key) == 33 or len(key) == 65)):
         return key
     assert(False)
 
 
 def check_script(script):
     if (type(script) is str):
         script = hex_str_to_bytes(script)  # Assuming this is hex string
     if (type(script) is bytes or type(script) is CScript):
         return script
     assert(False)
diff --git a/test/functional/test_framework/messages.py b/test/functional/test_framework/messages.py
index 4febcdf88..f1151f23e 100755
--- a/test/functional/test_framework/messages.py
+++ b/test/functional/test_framework/messages.py
@@ -1,1207 +1,1207 @@
 #!/usr/bin/env python3
 # Copyright (c) 2010 ArtForz -- public domain half-a-node
 # Copyright (c) 2012 Jeff Garzik
 # Copyright (c) 2010-2017 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Bitcoin test framework primitive and message strcutures
 
 CBlock, CTransaction, CBlockHeader, CTxIn, CTxOut, etc....:
     data structures that should map to corresponding structures in
     bitcoin/primitives
 
 msg_block, msg_tx, msg_headers, etc.:
     data structures that represent network messages
 
 ser_*, deser_*: functions that handle serialization/deserialization."""
 from codecs import encode
 import copy
 import hashlib
 from io import BytesIO
 import random
 import socket
 import struct
 import time
 
 from test_framework.siphash import siphash256
-from test_framework.util import hex_str_to_bytes, bytes_to_hex_str, wait_until
+from test_framework.util import hex_str_to_bytes, bytes_to_hex_str
 
 MIN_VERSION_SUPPORTED = 60001
 # past bip-31 for ping/pong
 MY_VERSION = 70014
 MY_SUBVERSION = b"/python-mininode-tester:0.0.3/"
 # from version 70001 onwards, fRelay should be appended to version messages (BIP37)
 MY_RELAY = 1
 
 MAX_INV_SZ = 50000
 MAX_BLOCK_BASE_SIZE = 1000000
 
 # 1 BCH in satoshis
 COIN = 100000000
 
 NODE_NETWORK = (1 << 0)
 # NODE_GETUTXO = (1 << 1)
 NODE_BLOOM = (1 << 2)
 NODE_WITNESS = (1 << 3)
 NODE_XTHIN = (1 << 4)
 NODE_BITCOIN_CASH = (1 << 5)
 NODE_NETWORK_LIMITED = (1 << 10)
 
 # Howmuch data will be read from the network at once
 READ_BUFFER_SIZE = 8192
 
 # Serialization/deserialization tools
 
 
 def sha256(s):
     return hashlib.new('sha256', s).digest()
 
 
 def ripemd160(s):
     return hashlib.new('ripemd160', s).digest()
 
 
 def hash256(s):
     return sha256(sha256(s))
 
 
 def ser_compact_size(l):
     r = b""
     if l < 253:
         r = struct.pack("B", l)
     elif l < 0x10000:
         r = struct.pack("<BH", 253, l)
     elif l < 0x100000000:
         r = struct.pack("<BI", 254, l)
     else:
         r = struct.pack("<BQ", 255, l)
     return r
 
 
 def deser_compact_size(f):
     nit = struct.unpack("<B", f.read(1))[0]
     if nit == 253:
         nit = struct.unpack("<H", f.read(2))[0]
     elif nit == 254:
         nit = struct.unpack("<I", f.read(4))[0]
     elif nit == 255:
         nit = struct.unpack("<Q", f.read(8))[0]
     return nit
 
 
 def deser_string(f):
     nit = deser_compact_size(f)
     return f.read(nit)
 
 
 def ser_string(s):
     return ser_compact_size(len(s)) + s
 
 
 def deser_uint256(f):
     r = 0
     for i in range(8):
         t = struct.unpack("<I", f.read(4))[0]
         r += t << (i * 32)
     return r
 
 
 def ser_uint256(u):
     rs = b""
     for i in range(8):
         rs += struct.pack("<I", u & 0xFFFFFFFF)
         u >>= 32
     return rs
 
 
 def uint256_from_str(s):
     r = 0
     t = struct.unpack("<IIIIIIII", s[:32])
     for i in range(8):
         r += t[i] << (i * 32)
     return r
 
 
 def uint256_from_compact(c):
     nbytes = (c >> 24) & 0xFF
     v = (c & 0xFFFFFF) << (8 * (nbytes - 3))
     return v
 
 
 def deser_vector(f, c):
     nit = deser_compact_size(f)
     r = []
     for i in range(nit):
         t = c()
         t.deserialize(f)
         r.append(t)
     return r
 
 
 # ser_function_name: Allow for an alternate serialization function on the
 # entries in the vector.
 def ser_vector(l, ser_function_name=None):
     r = ser_compact_size(len(l))
     for i in l:
         if ser_function_name:
             r += getattr(i, ser_function_name)()
         else:
             r += i.serialize()
     return r
 
 
 def deser_uint256_vector(f):
     nit = deser_compact_size(f)
     r = []
     for i in range(nit):
         t = deser_uint256(f)
         r.append(t)
     return r
 
 
 def ser_uint256_vector(l):
     r = ser_compact_size(len(l))
     for i in l:
         r += ser_uint256(i)
     return r
 
 
 def deser_string_vector(f):
     nit = deser_compact_size(f)
     r = []
     for i in range(nit):
         t = deser_string(f)
         r.append(t)
     return r
 
 
 def ser_string_vector(l):
     r = ser_compact_size(len(l))
     for sv in l:
         r += ser_string(sv)
     return r
 
 
 def deser_int_vector(f):
     nit = deser_compact_size(f)
     r = []
     for i in range(nit):
         t = struct.unpack("<i", f.read(4))[0]
         r.append(t)
     return r
 
 
 def ser_int_vector(l):
     r = ser_compact_size(len(l))
     for i in l:
         r += struct.pack("<i", i)
     return r
 
 # Deserialize from a hex string representation (eg from RPC)
 
 
 def FromHex(obj, hex_string):
     obj.deserialize(BytesIO(hex_str_to_bytes(hex_string)))
     return obj
 
 # Convert a binary-serializable object to hex (eg for submission via RPC)
 
 
 def ToHex(obj):
     return bytes_to_hex_str(obj.serialize())
 
 # Objects that map to bitcoind objects, which can be serialized/deserialized
 
 
 class CAddress():
     def __init__(self):
         self.time = 0
         self.nServices = 1
         self.pchReserved = b"\x00" * 10 + b"\xff" * 2
         self.ip = "0.0.0.0"
         self.port = 0
 
     def deserialize(self, f, with_time=True):
         if with_time:
             self.time = struct.unpack("<i", f.read(4))[0]
         self.nServices = struct.unpack("<Q", f.read(8))[0]
         self.pchReserved = f.read(12)
         self.ip = socket.inet_ntoa(f.read(4))
         self.port = struct.unpack(">H", f.read(2))[0]
 
     def serialize(self, with_time=True):
         r = b""
         if with_time:
             r += struct.pack("<i", self.time)
         r += struct.pack("<Q", self.nServices)
         r += self.pchReserved
         r += socket.inet_aton(self.ip)
         r += struct.pack(">H", self.port)
         return r
 
     def __repr__(self):
         return "CAddress(nServices=%i ip=%s port=%i)" % (self.nServices,
                                                          self.ip, self.port)
 
 
 class CInv():
     typemap = {
         0: "Error",
         1: "TX",
         2: "Block",
         4: "CompactBlock"
     }
 
     def __init__(self, t=0, h=0):
         self.type = t
         self.hash = h
 
     def deserialize(self, f):
         self.type = struct.unpack("<i", f.read(4))[0]
         self.hash = deser_uint256(f)
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.type)
         r += ser_uint256(self.hash)
         return r
 
     def __repr__(self):
         return "CInv(type=%s hash=%064x)" \
             % (self.typemap[self.type], self.hash)
 
 
 class CBlockLocator():
     def __init__(self):
         self.nVersion = MY_VERSION
         self.vHave = []
 
     def deserialize(self, f):
         self.nVersion = struct.unpack("<i", f.read(4))[0]
         self.vHave = deser_uint256_vector(f)
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.nVersion)
         r += ser_uint256_vector(self.vHave)
         return r
 
     def __repr__(self):
         return "CBlockLocator(nVersion=%i vHave=%s)" \
             % (self.nVersion, repr(self.vHave))
 
 
 class COutPoint():
     def __init__(self, hash=0, n=0):
         self.hash = hash
         self.n = n
 
     def deserialize(self, f):
         self.hash = deser_uint256(f)
         self.n = struct.unpack("<I", f.read(4))[0]
 
     def serialize(self):
         r = b""
         r += ser_uint256(self.hash)
         r += struct.pack("<I", self.n)
         return r
 
     def __repr__(self):
         return "COutPoint(hash=%064x n=%i)" % (self.hash, self.n)
 
 
 class CTxIn():
     def __init__(self, outpoint=None, scriptSig=b"", nSequence=0):
         if outpoint is None:
             self.prevout = COutPoint()
         else:
             self.prevout = outpoint
         self.scriptSig = scriptSig
         self.nSequence = nSequence
 
     def deserialize(self, f):
         self.prevout = COutPoint()
         self.prevout.deserialize(f)
         self.scriptSig = deser_string(f)
         self.nSequence = struct.unpack("<I", f.read(4))[0]
 
     def serialize(self):
         r = b""
         r += self.prevout.serialize()
         r += ser_string(self.scriptSig)
         r += struct.pack("<I", self.nSequence)
         return r
 
     def __repr__(self):
         return "CTxIn(prevout=%s scriptSig=%s nSequence=%i)" \
             % (repr(self.prevout), bytes_to_hex_str(self.scriptSig),
                self.nSequence)
 
 
 class CTxOut():
     def __init__(self, nValue=0, scriptPubKey=b""):
         self.nValue = nValue
         self.scriptPubKey = scriptPubKey
 
     def deserialize(self, f):
         self.nValue = struct.unpack("<q", f.read(8))[0]
         self.scriptPubKey = deser_string(f)
 
     def serialize(self):
         r = b""
         r += struct.pack("<q", self.nValue)
         r += ser_string(self.scriptPubKey)
         return r
 
     def __repr__(self):
         return "CTxOut(nValue=%i.%08i scriptPubKey=%s)" \
             % (self.nValue // COIN, self.nValue % COIN,
                bytes_to_hex_str(self.scriptPubKey))
 
 
 class CTransaction():
     def __init__(self, tx=None):
         if tx is None:
             self.nVersion = 1
             self.vin = []
             self.vout = []
             self.nLockTime = 0
             self.sha256 = None
             self.hash = None
         else:
             self.nVersion = tx.nVersion
             self.vin = copy.deepcopy(tx.vin)
             self.vout = copy.deepcopy(tx.vout)
             self.nLockTime = tx.nLockTime
             self.sha256 = tx.sha256
             self.hash = tx.hash
 
     def deserialize(self, f):
         self.nVersion = struct.unpack("<i", f.read(4))[0]
         self.vin = deser_vector(f, CTxIn)
         self.vout = deser_vector(f, CTxOut)
         self.nLockTime = struct.unpack("<I", f.read(4))[0]
         self.sha256 = None
         self.hash = None
 
     def billable_size(self):
         """
         Returns the size used for billing the against the transaction
         """
         return len(self.serialize())
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.nVersion)
         r += ser_vector(self.vin)
         r += ser_vector(self.vout)
         r += struct.pack("<I", self.nLockTime)
         return r
 
     # Recalculate the txid
     def rehash(self):
         self.sha256 = None
         self.calc_sha256()
 
     # self.sha256 and self.hash -- those are expected to be the txid.
     def calc_sha256(self):
         if self.sha256 is None:
             self.sha256 = uint256_from_str(hash256(self.serialize()))
         self.hash = encode(
             hash256(self.serialize())[::-1], 'hex_codec').decode('ascii')
 
     def get_id(self):
         # For now, just forward the hash.
         self.calc_sha256()
         return self.hash
 
     def is_valid(self):
         self.calc_sha256()
         for tout in self.vout:
             if tout.nValue < 0 or tout.nValue > 21000000 * COIN:
                 return False
         return True
 
     def __repr__(self):
         return "CTransaction(nVersion=%i vin=%s vout=%s nLockTime=%i)" \
             % (self.nVersion, repr(self.vin), repr(self.vout), self.nLockTime)
 
 
 class CBlockHeader():
     def __init__(self, header=None):
         if header is None:
             self.set_null()
         else:
             self.nVersion = header.nVersion
             self.hashPrevBlock = header.hashPrevBlock
             self.hashMerkleRoot = header.hashMerkleRoot
             self.nTime = header.nTime
             self.nBits = header.nBits
             self.nNonce = header.nNonce
             self.sha256 = header.sha256
             self.hash = header.hash
             self.calc_sha256()
 
     def set_null(self):
         self.nVersion = 1
         self.hashPrevBlock = 0
         self.hashMerkleRoot = 0
         self.nTime = 0
         self.nBits = 0
         self.nNonce = 0
         self.sha256 = None
         self.hash = None
 
     def deserialize(self, f):
         self.nVersion = struct.unpack("<i", f.read(4))[0]
         self.hashPrevBlock = deser_uint256(f)
         self.hashMerkleRoot = deser_uint256(f)
         self.nTime = struct.unpack("<I", f.read(4))[0]
         self.nBits = struct.unpack("<I", f.read(4))[0]
         self.nNonce = struct.unpack("<I", f.read(4))[0]
         self.sha256 = None
         self.hash = None
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.nVersion)
         r += ser_uint256(self.hashPrevBlock)
         r += ser_uint256(self.hashMerkleRoot)
         r += struct.pack("<I", self.nTime)
         r += struct.pack("<I", self.nBits)
         r += struct.pack("<I", self.nNonce)
         return r
 
     def calc_sha256(self):
         if self.sha256 is None:
             r = b""
             r += struct.pack("<i", self.nVersion)
             r += ser_uint256(self.hashPrevBlock)
             r += ser_uint256(self.hashMerkleRoot)
             r += struct.pack("<I", self.nTime)
             r += struct.pack("<I", self.nBits)
             r += struct.pack("<I", self.nNonce)
             self.sha256 = uint256_from_str(hash256(r))
             self.hash = encode(hash256(r)[::-1], 'hex_codec').decode('ascii')
 
     def rehash(self):
         self.sha256 = None
         self.calc_sha256()
         return self.sha256
 
     def __repr__(self):
         return "CBlockHeader(nVersion=%i hashPrevBlock=%064x hashMerkleRoot=%064x nTime=%s nBits=%08x nNonce=%08x)" \
             % (self.nVersion, self.hashPrevBlock, self.hashMerkleRoot,
                time.ctime(self.nTime), self.nBits, self.nNonce)
 
 
 class CBlock(CBlockHeader):
     def __init__(self, header=None):
         super(CBlock, self).__init__(header)
         self.vtx = []
 
     def deserialize(self, f):
         super(CBlock, self).deserialize(f)
         self.vtx = deser_vector(f, CTransaction)
 
     def serialize(self):
         r = b""
         r += super(CBlock, self).serialize()
         r += ser_vector(self.vtx)
         return r
 
     # Calculate the merkle root given a vector of transaction hashes
     def get_merkle_root(self, hashes):
         while len(hashes) > 1:
             newhashes = []
             for i in range(0, len(hashes), 2):
                 i2 = min(i + 1, len(hashes) - 1)
                 newhashes.append(hash256(hashes[i] + hashes[i2]))
             hashes = newhashes
         return uint256_from_str(hashes[0])
 
     def calc_merkle_root(self):
         hashes = []
         for tx in self.vtx:
             tx.calc_sha256()
             hashes.append(ser_uint256(tx.sha256))
         return self.get_merkle_root(hashes)
 
     def is_valid(self):
         self.calc_sha256()
         target = uint256_from_compact(self.nBits)
         if self.sha256 > target:
             return False
         for tx in self.vtx:
             if not tx.is_valid():
                 return False
         if self.calc_merkle_root() != self.hashMerkleRoot:
             return False
         return True
 
     def solve(self):
         self.rehash()
         target = uint256_from_compact(self.nBits)
         while self.sha256 > target:
             self.nNonce += 1
             self.rehash()
 
     def __repr__(self):
         return "CBlock(nVersion=%i hashPrevBlock=%064x hashMerkleRoot=%064x nTime=%s nBits=%08x nNonce=%08x vtx=%s)" \
             % (self.nVersion, self.hashPrevBlock, self.hashMerkleRoot,
                time.ctime(self.nTime), self.nBits, self.nNonce, repr(self.vtx))
 
 
 class PrefilledTransaction():
     def __init__(self, index=0, tx=None):
         self.index = index
         self.tx = tx
 
     def deserialize(self, f):
         self.index = deser_compact_size(f)
         self.tx = CTransaction()
         self.tx.deserialize(f)
 
     def serialize(self):
         r = b""
         r += ser_compact_size(self.index)
         r += self.tx.serialize()
         return r
 
     def __repr__(self):
         return "PrefilledTransaction(index=%d, tx=%s)" % (self.index, repr(self.tx))
 
 # This is what we send on the wire, in a cmpctblock message.
 
 
 class P2PHeaderAndShortIDs():
     def __init__(self):
         self.header = CBlockHeader()
         self.nonce = 0
         self.shortids_length = 0
         self.shortids = []
         self.prefilled_txn_length = 0
         self.prefilled_txn = []
 
     def deserialize(self, f):
         self.header.deserialize(f)
         self.nonce = struct.unpack("<Q", f.read(8))[0]
         self.shortids_length = deser_compact_size(f)
         for i in range(self.shortids_length):
             # shortids are defined to be 6 bytes in the spec, so append
             # two zero bytes and read it in as an 8-byte number
             self.shortids.append(
                 struct.unpack("<Q", f.read(6) + b'\x00\x00')[0])
         self.prefilled_txn = deser_vector(f, PrefilledTransaction)
         self.prefilled_txn_length = len(self.prefilled_txn)
 
     def serialize(self):
         r = b""
         r += self.header.serialize()
         r += struct.pack("<Q", self.nonce)
         r += ser_compact_size(self.shortids_length)
         for x in self.shortids:
             # We only want the first 6 bytes
             r += struct.pack("<Q", x)[0:6]
         r += ser_vector(self.prefilled_txn)
         return r
 
     def __repr__(self):
         return "P2PHeaderAndShortIDs(header=%s, nonce=%d, shortids_length=%d, shortids=%s, prefilled_txn_length=%d, prefilledtxn=%s" % (repr(self.header), self.nonce, self.shortids_length, repr(self.shortids), self.prefilled_txn_length, repr(self.prefilled_txn))
 
 # Calculate the BIP 152-compact blocks shortid for a given transaction hash
 
 
 def calculate_shortid(k0, k1, tx_hash):
     expected_shortid = siphash256(k0, k1, tx_hash)
     expected_shortid &= 0x0000ffffffffffff
     return expected_shortid
 
 # This version gets rid of the array lengths, and reinterprets the differential
 # encoding into indices that can be used for lookup.
 
 
 class HeaderAndShortIDs():
     def __init__(self, p2pheaders_and_shortids=None):
         self.header = CBlockHeader()
         self.nonce = 0
         self.shortids = []
         self.prefilled_txn = []
 
         if p2pheaders_and_shortids != None:
             self.header = p2pheaders_and_shortids.header
             self.nonce = p2pheaders_and_shortids.nonce
             self.shortids = p2pheaders_and_shortids.shortids
             last_index = -1
             for x in p2pheaders_and_shortids.prefilled_txn:
                 self.prefilled_txn.append(
                     PrefilledTransaction(x.index + last_index + 1, x.tx))
                 last_index = self.prefilled_txn[-1].index
 
     def to_p2p(self):
         ret = P2PHeaderAndShortIDs()
         ret.header = self.header
         ret.nonce = self.nonce
         ret.shortids_length = len(self.shortids)
         ret.shortids = self.shortids
         ret.prefilled_txn_length = len(self.prefilled_txn)
         ret.prefilled_txn = []
         last_index = -1
         for x in self.prefilled_txn:
             ret.prefilled_txn.append(
                 PrefilledTransaction(x.index - last_index - 1, x.tx))
             last_index = x.index
         return ret
 
     def get_siphash_keys(self):
         header_nonce = self.header.serialize()
         header_nonce += struct.pack("<Q", self.nonce)
         hash_header_nonce_as_str = sha256(header_nonce)
         key0 = struct.unpack("<Q", hash_header_nonce_as_str[0:8])[0]
         key1 = struct.unpack("<Q", hash_header_nonce_as_str[8:16])[0]
         return [key0, key1]
 
     # Version 2 compact blocks use wtxid in shortids (rather than txid)
     def initialize_from_block(self, block, nonce=0, prefill_list=[0]):
         self.header = CBlockHeader(block)
         self.nonce = nonce
         self.prefilled_txn = [PrefilledTransaction(i, block.vtx[i])
                               for i in prefill_list]
         self.shortids = []
         [k0, k1] = self.get_siphash_keys()
         for i in range(len(block.vtx)):
             if i not in prefill_list:
                 tx_hash = block.vtx[i].sha256
                 self.shortids.append(calculate_shortid(k0, k1, tx_hash))
 
     def __repr__(self):
         return "HeaderAndShortIDs(header=%s, nonce=%d, shortids=%s, prefilledtxn=%s" % (repr(self.header), self.nonce, repr(self.shortids), repr(self.prefilled_txn))
 
 
 class BlockTransactionsRequest():
 
     def __init__(self, blockhash=0, indexes=None):
         self.blockhash = blockhash
         self.indexes = indexes if indexes != None else []
 
     def deserialize(self, f):
         self.blockhash = deser_uint256(f)
         indexes_length = deser_compact_size(f)
         for i in range(indexes_length):
             self.indexes.append(deser_compact_size(f))
 
     def serialize(self):
         r = b""
         r += ser_uint256(self.blockhash)
         r += ser_compact_size(len(self.indexes))
         for x in self.indexes:
             r += ser_compact_size(x)
         return r
 
     # helper to set the differentially encoded indexes from absolute ones
     def from_absolute(self, absolute_indexes):
         self.indexes = []
         last_index = -1
         for x in absolute_indexes:
             self.indexes.append(x - last_index - 1)
             last_index = x
 
     def to_absolute(self):
         absolute_indexes = []
         last_index = -1
         for x in self.indexes:
             absolute_indexes.append(x + last_index + 1)
             last_index = absolute_indexes[-1]
         return absolute_indexes
 
     def __repr__(self):
         return "BlockTransactionsRequest(hash=%064x indexes=%s)" % (self.blockhash, repr(self.indexes))
 
 
 class BlockTransactions():
 
     def __init__(self, blockhash=0, transactions=None):
         self.blockhash = blockhash
         self.transactions = transactions if transactions != None else []
 
     def deserialize(self, f):
         self.blockhash = deser_uint256(f)
         self.transactions = deser_vector(f, CTransaction)
 
     def serialize(self):
         r = b""
         r += ser_uint256(self.blockhash)
         r += ser_vector(self.transactions)
         return r
 
     def __repr__(self):
         return "BlockTransactions(hash=%064x transactions=%s)" % (self.blockhash, repr(self.transactions))
 
 
 # Objects that correspond to messages on the wire
 class msg_version():
     command = b"version"
 
     def __init__(self):
         self.nVersion = MY_VERSION
         self.nServices = 1
         self.nTime = int(time.time())
         self.addrTo = CAddress()
         self.addrFrom = CAddress()
         self.nNonce = random.getrandbits(64)
         self.strSubVer = MY_SUBVERSION
         self.nStartingHeight = -1
         self.nRelay = MY_RELAY
 
     def deserialize(self, f):
         self.nVersion = struct.unpack("<i", f.read(4))[0]
         if self.nVersion == 10300:
             self.nVersion = 300
         self.nServices = struct.unpack("<Q", f.read(8))[0]
         self.nTime = struct.unpack("<q", f.read(8))[0]
         self.addrTo = CAddress()
         self.addrTo.deserialize(f, False)
 
         if self.nVersion >= 106:
             self.addrFrom = CAddress()
             self.addrFrom.deserialize(f, False)
             self.nNonce = struct.unpack("<Q", f.read(8))[0]
             self.strSubVer = deser_string(f)
         else:
             self.addrFrom = None
             self.nNonce = None
             self.strSubVer = None
             self.nStartingHeight = None
 
         if self.nVersion >= 209:
             self.nStartingHeight = struct.unpack("<i", f.read(4))[0]
         else:
             self.nStartingHeight = None
 
         if self.nVersion >= 70001:
             # Relay field is optional for version 70001 onwards
             try:
                 self.nRelay = struct.unpack("<b", f.read(1))[0]
             except:
                 self.nRelay = 0
         else:
             self.nRelay = 0
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.nVersion)
         r += struct.pack("<Q", self.nServices)
         r += struct.pack("<q", self.nTime)
         r += self.addrTo.serialize(False)
         r += self.addrFrom.serialize(False)
         r += struct.pack("<Q", self.nNonce)
         r += ser_string(self.strSubVer)
         r += struct.pack("<i", self.nStartingHeight)
         r += struct.pack("<b", self.nRelay)
         return r
 
     def __repr__(self):
         return 'msg_version(nVersion=%i nServices=%i nTime=%s addrTo=%s addrFrom=%s nNonce=0x%016X strSubVer=%s nStartingHeight=%i nRelay=%i)' \
             % (self.nVersion, self.nServices, time.ctime(self.nTime),
                repr(self.addrTo), repr(self.addrFrom), self.nNonce,
                self.strSubVer, self.nStartingHeight, self.nRelay)
 
 
 class msg_verack():
     command = b"verack"
 
     def __init__(self):
         pass
 
     def deserialize(self, f):
         pass
 
     def serialize(self):
         return b""
 
     def __repr__(self):
         return "msg_verack()"
 
 
 class msg_addr():
     command = b"addr"
 
     def __init__(self):
         self.addrs = []
 
     def deserialize(self, f):
         self.addrs = deser_vector(f, CAddress)
 
     def serialize(self):
         return ser_vector(self.addrs)
 
     def __repr__(self):
         return "msg_addr(addrs=%s)" % (repr(self.addrs))
 
 
 class msg_inv():
     command = b"inv"
 
     def __init__(self, inv=None):
         if inv is None:
             self.inv = []
         else:
             self.inv = inv
 
     def deserialize(self, f):
         self.inv = deser_vector(f, CInv)
 
     def serialize(self):
         return ser_vector(self.inv)
 
     def __repr__(self):
         return "msg_inv(inv=%s)" % (repr(self.inv))
 
 
 class msg_getdata():
     command = b"getdata"
 
     def __init__(self, inv=None):
         self.inv = inv if inv != None else []
 
     def deserialize(self, f):
         self.inv = deser_vector(f, CInv)
 
     def serialize(self):
         return ser_vector(self.inv)
 
     def __repr__(self):
         return "msg_getdata(inv=%s)" % (repr(self.inv))
 
 
 class msg_getblocks():
     command = b"getblocks"
 
     def __init__(self):
         self.locator = CBlockLocator()
         self.hashstop = 0
 
     def deserialize(self, f):
         self.locator = CBlockLocator()
         self.locator.deserialize(f)
         self.hashstop = deser_uint256(f)
 
     def serialize(self):
         r = b""
         r += self.locator.serialize()
         r += ser_uint256(self.hashstop)
         return r
 
     def __repr__(self):
         return "msg_getblocks(locator=%s hashstop=%064x)" \
             % (repr(self.locator), self.hashstop)
 
 
 class msg_tx():
     command = b"tx"
 
     def __init__(self, tx=CTransaction()):
         self.tx = tx
 
     def deserialize(self, f):
         self.tx.deserialize(f)
 
     def serialize(self):
         return self.tx.serialize()
 
     def __repr__(self):
         return "msg_tx(tx=%s)" % (repr(self.tx))
 
 
 class msg_block():
     command = b"block"
 
     def __init__(self, block=None):
         if block is None:
             self.block = CBlock()
         else:
             self.block = block
 
     def deserialize(self, f):
         self.block.deserialize(f)
 
     def serialize(self):
         return self.block.serialize()
 
     def __repr__(self):
         return "msg_block(block=%s)" % (repr(self.block))
 
 # for cases where a user needs tighter control over what is sent over the wire
 # note that the user must supply the name of the command, and the data
 
 
 class msg_generic():
     def __init__(self, command, data=None):
         self.command = command
         self.data = data
 
     def serialize(self):
         return self.data
 
     def __repr__(self):
         return "msg_generic()"
 
 
 class msg_getaddr():
     command = b"getaddr"
 
     def __init__(self):
         pass
 
     def deserialize(self, f):
         pass
 
     def serialize(self):
         return b""
 
     def __repr__(self):
         return "msg_getaddr()"
 
 
 class msg_ping():
     command = b"ping"
 
     def __init__(self, nonce=0):
         self.nonce = nonce
 
     def deserialize(self, f):
         self.nonce = struct.unpack("<Q", f.read(8))[0]
 
     def serialize(self):
         r = b""
         r += struct.pack("<Q", self.nonce)
         return r
 
     def __repr__(self):
         return "msg_ping(nonce=%08x)" % self.nonce
 
 
 class msg_pong():
     command = b"pong"
 
     def __init__(self, nonce=0):
         self.nonce = nonce
 
     def deserialize(self, f):
         self.nonce = struct.unpack("<Q", f.read(8))[0]
 
     def serialize(self):
         r = b""
         r += struct.pack("<Q", self.nonce)
         return r
 
     def __repr__(self):
         return "msg_pong(nonce=%08x)" % self.nonce
 
 
 class msg_mempool():
     command = b"mempool"
 
     def __init__(self):
         pass
 
     def deserialize(self, f):
         pass
 
     def serialize(self):
         return b""
 
     def __repr__(self):
         return "msg_mempool()"
 
 
 class msg_sendheaders():
     command = b"sendheaders"
 
     def __init__(self):
         pass
 
     def deserialize(self, f):
         pass
 
     def serialize(self):
         return b""
 
     def __repr__(self):
         return "msg_sendheaders()"
 
 
 # getheaders message has
 # number of entries
 # vector of hashes
 # hash_stop (hash of last desired block header, 0 to get as many as possible)
 class msg_getheaders():
     command = b"getheaders"
 
     def __init__(self):
         self.locator = CBlockLocator()
         self.hashstop = 0
 
     def deserialize(self, f):
         self.locator = CBlockLocator()
         self.locator.deserialize(f)
         self.hashstop = deser_uint256(f)
 
     def serialize(self):
         r = b""
         r += self.locator.serialize()
         r += ser_uint256(self.hashstop)
         return r
 
     def __repr__(self):
         return "msg_getheaders(locator=%s, stop=%064x)" \
             % (repr(self.locator), self.hashstop)
 
 
 # headers message has
 # <count> <vector of block headers>
 class msg_headers():
     command = b"headers"
 
     def __init__(self, headers=None):
         self.headers = headers if headers is not None else []
 
     def deserialize(self, f):
         # comment in bitcoind indicates these should be deserialized as blocks
         blocks = deser_vector(f, CBlock)
         for x in blocks:
             self.headers.append(CBlockHeader(x))
 
     def serialize(self):
         blocks = [CBlock(x) for x in self.headers]
         return ser_vector(blocks)
 
     def __repr__(self):
         return "msg_headers(headers=%s)" % repr(self.headers)
 
 
 class msg_reject():
     command = b"reject"
     REJECT_MALFORMED = 1
 
     def __init__(self):
         self.message = b""
         self.code = 0
         self.reason = b""
         self.data = 0
 
     def deserialize(self, f):
         self.message = deser_string(f)
         self.code = struct.unpack("<B", f.read(1))[0]
         self.reason = deser_string(f)
         if (self.code != self.REJECT_MALFORMED and
                 (self.message == b"block" or self.message == b"tx")):
             self.data = deser_uint256(f)
 
     def serialize(self):
         r = ser_string(self.message)
         r += struct.pack("<B", self.code)
         r += ser_string(self.reason)
         if (self.code != self.REJECT_MALFORMED and
                 (self.message == b"block" or self.message == b"tx")):
             r += ser_uint256(self.data)
         return r
 
     def __repr__(self):
         return "msg_reject: %s %d %s [%064x]" \
             % (self.message, self.code, self.reason, self.data)
 
 
 class msg_feefilter():
     command = b"feefilter"
 
     def __init__(self, feerate=0):
         self.feerate = feerate
 
     def deserialize(self, f):
         self.feerate = struct.unpack("<Q", f.read(8))[0]
 
     def serialize(self):
         r = b""
         r += struct.pack("<Q", self.feerate)
         return r
 
     def __repr__(self):
         return "msg_feefilter(feerate=%08x)" % self.feerate
 
 
 class msg_sendcmpct():
     command = b"sendcmpct"
 
     def __init__(self):
         self.announce = False
         self.version = 1
 
     def deserialize(self, f):
         self.announce = struct.unpack("<?", f.read(1))[0]
         self.version = struct.unpack("<Q", f.read(8))[0]
 
     def serialize(self):
         r = b""
         r += struct.pack("<?", self.announce)
         r += struct.pack("<Q", self.version)
         return r
 
     def __repr__(self):
         return "msg_sendcmpct(announce=%s, version=%lu)" % (self.announce, self.version)
 
 
 class msg_cmpctblock():
     command = b"cmpctblock"
 
     def __init__(self, header_and_shortids=None):
         self.header_and_shortids = header_and_shortids
 
     def deserialize(self, f):
         self.header_and_shortids = P2PHeaderAndShortIDs()
         self.header_and_shortids.deserialize(f)
 
     def serialize(self):
         r = b""
         r += self.header_and_shortids.serialize()
         return r
 
     def __repr__(self):
         return "msg_cmpctblock(HeaderAndShortIDs=%s)" % repr(self.header_and_shortids)
 
 
 class msg_getblocktxn():
     command = b"getblocktxn"
 
     def __init__(self):
         self.block_txn_request = None
 
     def deserialize(self, f):
         self.block_txn_request = BlockTransactionsRequest()
         self.block_txn_request.deserialize(f)
 
     def serialize(self):
         r = b""
         r += self.block_txn_request.serialize()
         return r
 
     def __repr__(self):
         return "msg_getblocktxn(block_txn_request=%s)" % (repr(self.block_txn_request))
 
 
 class msg_blocktxn():
     command = b"blocktxn"
 
     def __init__(self):
         self.block_transactions = BlockTransactions()
 
     def deserialize(self, f):
         self.block_transactions.deserialize(f)
 
     def serialize(self):
         r = b""
         r += self.block_transactions.serialize()
         return r
 
     def __repr__(self):
         return "msg_blocktxn(block_transactions=%s)" % (repr(self.block_transactions))
diff --git a/test/functional/test_framework/test_node.py b/test/functional/test_framework/test_node.py
index 6c34b415e..7ecf951e6 100755
--- a/test/functional/test_framework/test_node.py
+++ b/test/functional/test_framework/test_node.py
@@ -1,305 +1,305 @@
 #!/usr/bin/env python3
 # Copyright (c) 2017 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Class for bitcoind node under test"""
 
 import decimal
 import errno
 import http.client
 import json
 import logging
 import os
 import re
 import subprocess
 import time
 
 from .authproxy import JSONRPCException
-from .mininode import COIN, ToHex, FromHex, CTransaction
+from .mininode import COIN, FromHex, CTransaction
 from .util import (
     assert_equal,
     get_rpc_proxy,
     rpc_url,
     wait_until,
     p2p_port,
 )
 
 # For Python 3.4 compatibility
 JSONDecodeError = getattr(json, "JSONDecodeError", ValueError)
 
 BITCOIND_PROC_WAIT_TIMEOUT = 60
 
 
 class TestNode():
     """A class for representing a bitcoind node under test.
 
     This class contains:
 
     - state about the node (whether it's running, etc)
     - a Python subprocess.Popen object representing the running process
     - an RPC connection to the node
     - one or more P2P connections to the node
 
     To make things easier for the test writer, any unrecognised messages will
     be dispatched to the RPC connection."""
 
     def __init__(self, i, dirname, extra_args, host, rpc_port, p2p_port, timewait, binary, stderr, mocktime, coverage_dir, use_cli=False):
         self.index = i
         self.datadir = os.path.join(dirname, "node" + str(i))
         self.host = host
         self.rpc_port = rpc_port
         self.p2p_port = p2p_port
         self.name = "testnode-{}".format(i)
         if timewait:
             self.rpc_timeout = timewait
         else:
             # Wait for up to 60 seconds for the RPC server to respond
             self.rpc_timeout = 60
         if binary is None:
             self.binary = os.getenv("BITCOIND", "bitcoind")
         else:
             self.binary = binary
         self.stderr = stderr
         self.coverage_dir = coverage_dir
         # Most callers will just need to add extra args to the standard list below. For those callers that need more flexibity, they can just set the args property directly.
         self.extra_args = extra_args
         self.args = [self.binary, "-datadir=" + self.datadir, "-server", "-keypool=1", "-discover=0", "-rest", "-logtimemicros",
                      "-debug", "-debugexclude=libevent", "-debugexclude=leveldb", "-mocktime=" + str(mocktime), "-uacomment=" + self.name]
 
         self.cli = TestNodeCLI(
             os.getenv("BITCOINCLI", "bitcoin-cli"), self.datadir)
         self.use_cli = use_cli
 
         self.running = False
         self.process = None
         self.rpc_connected = False
         self.rpc = None
         self.url = None
         self.relay_fee_cache = None
         self.log = logging.getLogger('TestFramework.node%d' % i)
 
         self.p2ps = []
 
     def __getattr__(self, name):
         """Dispatches any unrecognised messages to the RPC connection or a CLI instance."""
         if self.use_cli:
             return getattr(self.cli, name)
         else:
             assert self.rpc is not None, "Error: RPC not initialized"
             assert self.rpc_connected, "Error: No RPC connection"
             return getattr(self.rpc, name)
 
     def start(self, extra_args=None, stderr=None, *args, **kwargs):
         """Start the node."""
         if extra_args is None:
             extra_args = self.extra_args
         if stderr is None:
             stderr = self.stderr
         self.process = subprocess.Popen(
             self.args + extra_args, stderr=stderr, *args, **kwargs)
         self.running = True
         self.log.debug("bitcoind started, waiting for RPC to come up")
 
     def wait_for_rpc_connection(self):
         """Sets up an RPC connection to the bitcoind process. Returns False if unable to connect."""
         # Poll at a rate of four times per second
         poll_per_s = 4
         for _ in range(poll_per_s * self.rpc_timeout):
             assert self.process.poll(
             ) is None, "bitcoind exited with status %i during initialization" % self.process.returncode
             try:
                 self.rpc = get_rpc_proxy(rpc_url(self.datadir, self.host, self.rpc_port),
                                          self.index, timeout=self.rpc_timeout, coveragedir=self.coverage_dir)
                 self.rpc.getblockcount()
                 # If the call to getblockcount() succeeds then the RPC connection is up
                 self.rpc_connected = True
                 self.url = self.rpc.url
                 self.log.debug("RPC successfully started")
                 return
             except IOError as e:
                 if e.errno != errno.ECONNREFUSED:  # Port not yet open?
                     raise  # unknown IO error
             except JSONRPCException as e:  # Initialization phase
                 if e.error['code'] != -28:  # RPC in warmup?
                     raise  # unknown JSON RPC exception
             except ValueError as e:  # cookie file not found and no rpcuser or rpcassword. bitcoind still starting
                 if "No RPC credentials" not in str(e):
                     raise
             time.sleep(1.0 / poll_per_s)
         raise AssertionError("Unable to connect to bitcoind")
 
     def get_wallet_rpc(self, wallet_name):
         if self.use_cli:
             return self.cli("-rpcwallet={}".format(wallet_name))
         else:
             assert self.rpc_connected
             assert self.rpc
             wallet_path = "wallet/{}".format(wallet_name)
             return self.rpc / wallet_path
 
     def stop_node(self):
         """Stop the node."""
         if not self.running:
             return
         self.log.debug("Stopping node")
         try:
             self.stop()
         except http.client.CannotSendRequest:
             self.log.exception("Unable to stop node.")
         del self.p2ps[:]
 
     def is_node_stopped(self):
         """Checks whether the node has stopped.
 
         Returns True if the node has stopped. False otherwise.
         This method is responsible for freeing resources (self.process)."""
         if not self.running:
             return True
         return_code = self.process.poll()
         if return_code is None:
             return False
 
         # process has stopped. Assert that it didn't return an error code.
         assert_equal(return_code, 0)
         self.running = False
         self.process = None
         self.rpc_connected = False
         self.rpc = None
         self.log.debug("Node stopped")
         return True
 
     def wait_until_stopped(self, timeout=BITCOIND_PROC_WAIT_TIMEOUT):
         wait_until(self.is_node_stopped, timeout=timeout)
 
     def node_encrypt_wallet(self, passphrase):
         """"Encrypts the wallet.
 
         This causes bitcoind to shutdown, so this method takes
         care of cleaning up resources."""
         self.encryptwallet(passphrase)
         self.wait_until_stopped()
 
     def relay_fee(self, cached=True):
         if not self.relay_fee_cache or not cached:
             self.relay_fee_cache = self.getnetworkinfo()["relayfee"]
 
         return self.relay_fee_cache
 
     def calculate_fee(self, tx):
         # Relay fee is in satoshis per KB.  Thus the 1000, and the COIN added
         # to get back to an amount of satoshis.
         billable_size_estimate = tx.billable_size()
         # Add some padding for signatures
         # NOTE: Fees must be calculated before signatures are added,
         # so they will never be included in the billable_size above.
         billable_size_estimate += len(tx.vin) * 81
 
         return int(self.relay_fee() / 1000 * billable_size_estimate * COIN)
 
     def calculate_fee_from_txid(self, txid):
         ctx = FromHex(CTransaction(), self.getrawtransaction(txid))
         return self.calculate_fee(ctx)
 
     def add_p2p_connection(self, p2p_conn, *args, **kwargs):
         """Add a p2p connection to the node.
 
         This method adds the p2p connection to the self.p2ps list and also
         returns the connection to the caller."""
         if 'dstport' not in kwargs:
             kwargs['dstport'] = p2p_port(self.index)
         if 'dstaddr' not in kwargs:
             kwargs['dstaddr'] = '127.0.0.1'
 
         p2p_conn.peer_connect(*args, **kwargs)
         self.p2ps.append(p2p_conn)
 
         return p2p_conn
 
     @property
     def p2p(self):
         """Return the first p2p connection
 
         Convenience property - most tests only use a single p2p connection to each
         node, so this saves having to write node.p2ps[0] many times."""
         assert self.p2ps, "No p2p connection"
         return self.p2ps[0]
 
     def disconnect_p2ps(self):
         """Close all p2p connections to the node."""
         for p in self.p2ps:
             p.peer_disconnect()
         del self.p2ps[:]
 
 
 class TestNodeCLIAttr:
     def __init__(self, cli, command):
         self.cli = cli
         self.command = command
 
     def __call__(self, *args, **kwargs):
         return self.cli.send_cli(self.command, *args, **kwargs)
 
     def get_request(self, *args, **kwargs):
         return lambda: self(*args, **kwargs)
 
 
 class TestNodeCLI():
     """Interface to bitcoin-cli for an individual node"""
 
     def __init__(self, binary, datadir):
         self.args = []
         self.binary = binary
         self.datadir = datadir
         self.input = None
         self.log = logging.getLogger('TestFramework.bitcoincli')
 
     def __call__(self, *args, input=None):
         # TestNodeCLI is callable with bitcoin-cli command-line args
         cli = TestNodeCLI(self.binary, self.datadir)
         cli.args = [str(arg) for arg in args]
         cli.input = input
         return cli
 
     def __getattr__(self, command):
         return TestNodeCLIAttr(self, command)
 
     def batch(self, requests):
         results = []
         for request in requests:
             try:
                 results.append(dict(result=request()))
             except JSONRPCException as e:
                 results.append(dict(error=e))
         return results
 
     def send_cli(self, command, *args, **kwargs):
         """Run bitcoin-cli command. Deserializes returned string as python object."""
 
         pos_args = [str(arg) for arg in args]
         named_args = [str(key) + "=" + str(value)
                       for (key, value) in kwargs.items()]
         assert not (
             pos_args and named_args), "Cannot use positional arguments and named arguments in the same bitcoin-cli call"
 
         p_args = [self.binary, "-datadir=" + self.datadir] + self.args
         if named_args:
             p_args += ["-named"]
         p_args += [command] + pos_args + named_args
         self.log.debug("Running bitcoin-cli command: {}".format(command))
         process = subprocess.Popen(p_args, stdin=subprocess.PIPE,
                                    stdout=subprocess.PIPE, stderr=subprocess.PIPE, universal_newlines=True)
         cli_stdout, cli_stderr = process.communicate(input=self.input)
         returncode = process.poll()
         if returncode:
             match = re.match(
                 r'error code: ([-0-9]+)\nerror message:\n(.*)', cli_stderr)
             if match:
                 code, message = match.groups()
                 raise JSONRPCException(dict(code=int(code), message=message))
             # Ignore cli_stdout, raise with cli_stderr
             raise subprocess.CalledProcessError(
                 returncode, self.binary, output=cli_stderr)
         try:
             return json.loads(cli_stdout, parse_float=decimal.Decimal)
         except JSONDecodeError:
             return cli_stdout.rstrip("\n")
diff --git a/test/functional/test_framework/txtools.py b/test/functional/test_framework/txtools.py
index 06b38565e..a8abda430 100644
--- a/test/functional/test_framework/txtools.py
+++ b/test/functional/test_framework/txtools.py
@@ -1,71 +1,70 @@
 from .cdefs import MIN_TX_SIZE, MAX_TXOUT_PUBKEY_SCRIPT
 from .mininode import CTransaction, FromHex, ToHex, CTxOut
 from .script import OP_RETURN, CScript
 
 import random
-from binascii import hexlify, unhexlify
 
 
 def pad_tx(tx, pad_to_size=MIN_TX_SIZE):
     """
     Pad a transaction with op_return junk data until it is at least pad_to_size, or
     leave it alone if it's already bigger than that.
     """
     curr_size = len(tx.serialize())
     if curr_size >= pad_to_size:
         # Bail early txn is already big enough
         return
 
     # This code attempts to pad a transaction with opreturn vouts such that
     # it will be exactly pad_to_size.  In order to do this we have to create
     # vouts of size x (maximum OP_RETURN size - vout overhead), plus the final
     # one subsumes any runoff which would be less than vout overhead.
     #
     # There are two cases where this is not possible:
     # 1. The transaction size is between pad_to_size and pad_to_size - extrabytes
     # 2. The transaction is already greater than pad_to_size
     #
     # Visually:
     # | .. x  .. | .. x .. | .. x .. | .. x + desired_size % x |
     #    VOUT_1     VOUT_2    VOUT_3    VOUT_4
     # txout.value + txout.pk_script bytes + op_return
     extra_bytes = 8 + 1 + 1
     required_padding = pad_to_size - curr_size
     while required_padding > 0:
         # We need at least extra_bytes left over each time, or we can't
         # subsume the final (and possibly undersized) iteration of the loop
         padding_len = min(required_padding,
                           MAX_TXOUT_PUBKEY_SCRIPT - extra_bytes)
         assert padding_len >= 0, "Can't pad less than 0 bytes, trying {}".format(
             padding_len)
         # We will end up with less than 1 UTXO of bytes after this, add
         # them to this txn
         next_iteration_padding = required_padding - padding_len - extra_bytes
         if next_iteration_padding > 0 and next_iteration_padding < extra_bytes:
             padding_len += next_iteration_padding
 
         # If we're at exactly, or below, extra_bytes we don't want a 1 extra byte padding
         if padding_len <= extra_bytes:
             tx.vout.append(CTxOut(0, CScript([OP_RETURN])))
         else:
             # Subtract the overhead for the TxOut
             padding_len -= extra_bytes
             padding = random.randrange(
                 1 << 8 * padding_len - 2, 1 << 8 * padding_len - 1)
             tx.vout.append(
                 CTxOut(0, CScript([OP_RETURN, padding])))
 
         curr_size = len(tx.serialize())
         required_padding = pad_to_size - curr_size
     assert curr_size >= pad_to_size, "{} !>= {}".format(curr_size, pad_to_size)
     tx.rehash()
 
 
 def pad_raw_tx(rawtx_hex, min_size=MIN_TX_SIZE):
     """
     Pad a raw transaction with OP_RETURN data until it reaches at least min_size
     """
     tx = CTransaction()
     FromHex(tx, rawtx_hex)
     pad_tx(tx, min_size)
     return ToHex(tx)
diff --git a/test/functional/test_runner.py b/test/functional/test_runner.py
index 032f99b3e..bc6687472 100755
--- a/test/functional/test_runner.py
+++ b/test/functional/test_runner.py
@@ -1,721 +1,720 @@
 #!/usr/bin/env python3
 # Copyright (c) 2014-2016 The Bitcoin Core developers
 # Copyright (c) 2017 The Bitcoin developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Run regression test suite.
 
 This module calls down into individual test cases via subprocess. It will
 forward all unrecognized arguments onto the individual test scripts.
 
 Functional tests are disabled on Windows by default. Use --force to run them anyway.
 
 For a description of arguments recognized by test scripts, see
 `test/functional/test_framework/test_framework.py:BitcoinTestFramework.main`.
 
 """
 
 import argparse
 import configparser
 import datetime
 import os
 import time
 import shutil
-import signal
 import sys
 import subprocess
 import tempfile
 import re
 import logging
 import xml.etree.ElementTree as ET
 import json
 import threading
 import multiprocessing
 from queue import Queue, Empty
 
 # Formatting. Default colors to empty strings.
 BOLD, BLUE, RED, GREY = ("", ""), ("", ""), ("", ""), ("", "")
 try:
     # Make sure python thinks it can write unicode to its stdout
     "\u2713".encode("utf_8").decode(sys.stdout.encoding)
     TICK = "✓ "
     CROSS = "✖ "
     CIRCLE = "○ "
 except UnicodeDecodeError:
     TICK = "P "
     CROSS = "x "
     CIRCLE = "o "
 
 if os.name == 'posix':
     # primitive formatting on supported
     # terminal via ANSI escape sequences:
     BOLD = ('\033[0m', '\033[1m')
     BLUE = ('\033[0m', '\033[0;34m')
     RED = ('\033[0m', '\033[0;31m')
     GREY = ('\033[0m', '\033[1;30m')
 
 TEST_EXIT_PASSED = 0
 TEST_EXIT_SKIPPED = 77
 
 NON_SCRIPTS = [
     # These are python files that live in the functional tests directory, but are not test scripts.
     "combine_logs.py",
     "create_cache.py",
     "test_runner.py",
 ]
 
 TEST_PARAMS = {
     # Some test can be run with additional parameters.
     # When a test is listed here, the it  will be run without parameters
     # as well as with additional parameters listed here.
     # This:
     #    example "testName" : [["--param1", "--param2"] , ["--param3"]]
     # will run the test 3 times:
     #    testName
     #    testName --param1 --param2
     #    testname --param3
     "wallet_txn_doublespend.py": [["--mineblock"]],
     "wallet_txn_clone.py": [["--mineblock"]],
     "wallet_multiwallet.py": [["--usecli"]],
 }
 
 # Used to limit the number of tests, when list of tests is not provided on command line
 # When --extended is specified, we run all tests, otherwise
 # we only run a test if its execution time in seconds does not exceed EXTENDED_CUTOFF
 DEFAULT_EXTENDED_CUTOFF = 40
 DEFAULT_JOBS = (multiprocessing.cpu_count() // 3) + 1
 
 
 class TestCase():
     """
     Data structure to hold and run information necessary to launch a test case.
     """
 
     def __init__(self, test_num, test_case, tests_dir, tmpdir, flags=None):
         self.tests_dir = tests_dir
         self.tmpdir = tmpdir
         self.test_case = test_case
         self.test_num = test_num
         self.flags = flags
 
     def run(self, portseed_offset):
         t = self.test_case
         portseed = self.test_num + portseed_offset
         portseed_arg = ["--portseed={}".format(portseed)]
         log_stdout = tempfile.SpooledTemporaryFile(max_size=2**16)
         log_stderr = tempfile.SpooledTemporaryFile(max_size=2**16)
         test_argv = t.split()
         tmpdir = [os.path.join("--tmpdir=%s", "%s_%s") %
                   (self.tmpdir, re.sub(".py$", "", t), portseed)]
         name = t
         time0 = time.time()
         process = subprocess.Popen([os.path.join(self.tests_dir, test_argv[0])] + test_argv[1:] + self.flags + portseed_arg + tmpdir,
                                    universal_newlines=True,
                                    stdout=log_stdout,
                                    stderr=log_stderr)
 
         process.wait()
         log_stdout.seek(0), log_stderr.seek(0)
         [stdout, stderr] = [l.read().decode('utf-8')
                             for l in (log_stdout, log_stderr)]
         log_stdout.close(), log_stderr.close()
         if process.returncode == TEST_EXIT_PASSED and stderr == "":
             status = "Passed"
         elif process.returncode == TEST_EXIT_SKIPPED:
             status = "Skipped"
         else:
             status = "Failed"
 
         return TestResult(name, status, int(time.time() - time0), stdout, stderr)
 
 
 def on_ci():
     return os.getenv('TRAVIS') == 'true' or os.getenv('TEAMCITY_VERSION') != None
 
 
 def main():
     # Read config generated by configure.
     config = configparser.ConfigParser()
     configfile = os.path.join(os.path.abspath(
         os.path.dirname(__file__)), "..", "config.ini")
     config.read_file(open(configfile))
 
     src_dir = config["environment"]["SRCDIR"]
     build_dir = config["environment"]["BUILDDIR"]
     tests_dir = os.path.join(src_dir, 'test', 'functional')
 
     # Parse arguments and pass through unrecognised args
     parser = argparse.ArgumentParser(add_help=False,
                                      usage='%(prog)s [test_runner.py options] [script options] [scripts]',
                                      description=__doc__,
                                      epilog='''
     Help text and arguments for individual test script:''',
                                      formatter_class=argparse.RawTextHelpFormatter)
     parser.add_argument('--coverage', action='store_true',
                         help='generate a basic coverage report for the RPC interface')
     parser.add_argument(
         '--exclude', '-x', help='specify a comma-seperated-list of scripts to exclude. Do not include the .py extension in the name.')
     parser.add_argument('--extended', action='store_true',
                         help='run the extended test suite in addition to the basic tests')
     parser.add_argument('--cutoff', type=int, default=DEFAULT_EXTENDED_CUTOFF,
                         help='set the cutoff runtime for what tests get run')
     parser.add_argument('--force', '-f', action='store_true',
                         help='run tests even on platforms where they are disabled by default (e.g. windows).')
     parser.add_argument('--help', '-h', '-?',
                         action='store_true', help='print help text and exit')
     parser.add_argument('--jobs', '-j', type=int, default=DEFAULT_JOBS,
                         help='how many test scripts to run in parallel. Default=4.')
     parser.add_argument('--keepcache', '-k', action='store_true',
                         help='the default behavior is to flush the cache directory on startup. --keepcache retains the cache from the previous testrun.')
     parser.add_argument('--quiet', '-q', action='store_true',
                         help='only print results summary and failure logs')
     parser.add_argument('--tmpdirprefix', '-t',
                         default=tempfile.gettempdir(), help="Root directory for datadirs")
     parser.add_argument('--junitouput', '-ju',
                         default=os.path.join(build_dir, 'junit_results.xml'), help="file that will store JUnit formated test results.")
 
     args, unknown_args = parser.parse_known_args()
 
     # Create a set to store arguments and create the passon string
     tests = set(arg for arg in unknown_args if arg[:2] != "--")
     passon_args = [arg for arg in unknown_args if arg[:2] == "--"]
     passon_args.append("--configfile=%s" % configfile)
 
     # Set up logging
     logging_level = logging.INFO if args.quiet else logging.DEBUG
     logging.basicConfig(format='%(message)s', level=logging_level)
 
     # Create base test directory
     tmpdir = os.path.join("%s", "bitcoin_test_runner_%s") % (
         args.tmpdirprefix, datetime.datetime.now().strftime("%Y%m%d_%H%M%S"))
     os.makedirs(tmpdir)
 
     logging.debug("Temporary test directory at %s" % tmpdir)
 
     enable_wallet = config["components"].getboolean("ENABLE_WALLET")
     enable_utils = config["components"].getboolean("ENABLE_UTILS")
     enable_bitcoind = config["components"].getboolean("ENABLE_BITCOIND")
 
     if config["environment"]["EXEEXT"] == ".exe" and not args.force:
         # https://github.com/bitcoin/bitcoin/commit/d52802551752140cf41f0d9a225a43e84404d3e9
         # https://github.com/bitcoin/bitcoin/pull/5677#issuecomment-136646964
         print(
             "Tests currently disabled on Windows by default. Use --force option to enable")
         sys.exit(0)
 
     if not (enable_wallet and enable_utils and enable_bitcoind):
         print(
             "No functional tests to run. Wallet, utils, and bitcoind must all be enabled")
         print(
             "Rerun `configure` with -enable-wallet, -with-utils and -with-daemon and rerun make")
         sys.exit(0)
 
     # Build list of tests
     all_scripts = get_all_scripts_from_disk(tests_dir, NON_SCRIPTS)
 
     # Check all tests with parameters actually exist
     for test in TEST_PARAMS:
         if not test in all_scripts:
             print("ERROR: Test with parameter {} does not exist, check it has "
                   "not been renamed or deleted".format(test))
             sys.exit(1)
 
     if tests:
         # Individual tests have been specified. Run specified tests that exist
         # in the all_scripts list. Accept the name with or without .py
         # extension.
         test_list = [t for t in all_scripts if
                      (t in tests or re.sub(".py$", "", t) in tests)]
         cutoff = sys.maxsize  # do not cut off explicitly specified tests
     else:
         # No individual tests have been specified.
         # Run all tests that do not exceed
         test_list = all_scripts
         cutoff = args.cutoff
         if args.extended:
             cutoff = sys.maxsize
 
     # Remove the test cases that the user has explicitly asked to exclude.
     if args.exclude:
         for exclude_test in args.exclude.split(','):
             if exclude_test + ".py" in test_list:
                 test_list.remove(exclude_test + ".py")
 
     # Use and update timings from build_dir only if separate
     # build directory is used. We do not want to pollute source directory.
     build_timings = None
     if (src_dir != build_dir):
         build_timings = Timings(os.path.join(build_dir, 'timing.json'))
 
     # Always use timings from scr_dir if present
     src_timings = Timings(os.path.join(
         src_dir, "test", "functional", 'timing.json'))
 
     # Add test parameters and remove long running tests if needed
     test_list = get_tests_to_run(
         test_list, TEST_PARAMS, cutoff, src_timings, build_timings)
 
     if not test_list:
         print("No valid test scripts specified. Check that your test is in one "
               "of the test lists in test_runner.py, or run test_runner.py with no arguments to run all tests")
         sys.exit(0)
 
     if args.help:
         # Print help for test_runner.py, then print help of the first script
         # and exit.
         parser.print_help()
         subprocess.check_call(
             [os.path.join(tests_dir, test_list[0]), '-h'])
         sys.exit(0)
 
     if not args.keepcache:
         shutil.rmtree(os.path.join(build_dir, "test",
                                    "cache"), ignore_errors=True)
 
     run_tests(test_list, build_dir, tests_dir, args.junitouput,
               config["environment"]["EXEEXT"], tmpdir, args.jobs, args.coverage, passon_args, build_timings)
 
 
 def run_tests(test_list, build_dir, tests_dir, junitouput, exeext, tmpdir, num_jobs, enable_coverage=False, args=[], build_timings=None):
     # Warn if bitcoind is already running (unix only)
     try:
         pidofOutput = subprocess.check_output(["pidof", "bitcoind"])
         if pidofOutput is not None and pidofOutput != b'':
             print("%sWARNING!%s There is already a bitcoind process running on this system. Tests may fail unexpectedly due to resource contention!" % (
                 BOLD[1], BOLD[0]))
     except (OSError, subprocess.SubprocessError):
         pass
 
     # Warn if there is a cache directory
     cache_dir = os.path.join(build_dir, "test", "cache")
     if os.path.isdir(cache_dir):
         print("%sWARNING!%s There is a cache directory here: %s. If tests fail unexpectedly, try deleting the cache directory." % (
             BOLD[1], BOLD[0], cache_dir))
 
     # Set env vars
     if "BITCOIND" not in os.environ:
         os.environ["BITCOIND"] = os.path.join(
             build_dir, 'src', 'bitcoind' + exeext)
         os.environ["BITCOINCLI"] = os.path.join(
             build_dir, 'src', 'bitcoin-cli' + exeext)
 
     flags = [os.path.join("--srcdir={}".format(build_dir), "src")] + args
     flags.append("--cachedir=%s" % cache_dir)
 
     if enable_coverage:
         coverage = RPCCoverage()
         flags.append(coverage.flag)
         logging.debug("Initializing coverage directory at %s" % coverage.dir)
     else:
         coverage = None
 
     if len(test_list) > 1 and num_jobs > 1:
         # Populate cache
         try:
             subprocess.check_output(
                 [os.path.join(tests_dir, 'create_cache.py')] + flags + [os.path.join("--tmpdir=%s", "cache") % tmpdir])
         except Exception as e:
             print(e.output)
             raise e
 
     # Run Tests
     time0 = time.time()
     test_results = execute_test_processes(
         num_jobs, test_list, tests_dir, tmpdir, flags)
     runtime = int(time.time() - time0)
 
     max_len_name = len(max(test_list, key=len))
     print_results(test_results, max_len_name, runtime)
     save_results_as_junit(test_results, junitouput, runtime)
 
     if (build_timings is not None):
         build_timings.save_timings(test_results)
 
     if coverage:
         coverage.report_rpc_coverage()
 
         logging.debug("Cleaning up coverage data")
         coverage.cleanup()
 
     # Clear up the temp directory if all subdirectories are gone
     if not os.listdir(tmpdir):
         os.rmdir(tmpdir)
 
     all_passed = all(
         map(lambda test_result: test_result.was_successful, test_results))
 
     sys.exit(not all_passed)
 
 
 def execute_test_processes(num_jobs, test_list, tests_dir, tmpdir, flags):
     update_queue = Queue()
     job_queue = Queue()
     test_results = []
     poll_timeout = 10  # seconds
     # In case there is a graveyard of zombie bitcoinds, we can apply a
     # pseudorandom offset to hopefully jump over them.
     # (625 is PORT_RANGE/MAX_NODES)
     portseed_offset = int(time.time() * 1000) % 625
 
     ##
     # Define some helper functions we will need for threading.
     ##
 
     def handle_message(message, running_jobs):
         """
         handle_message handles a single message from handle_test_cases
         """
         if isinstance(message, TestCase):
             running_jobs.add(message.test_case)
             print("{}{}{} started".format(BOLD[1], message.test_case, BOLD[0]))
             return
 
         if isinstance(message, TestResult):
             test_result = message
 
             running_jobs.remove(test_result.name)
             test_results.append(test_result)
 
             if test_result.status == "Passed":
                 print("%s%s%s passed, Duration: %s s" % (
                     BOLD[1], test_result.name, BOLD[0], test_result.time))
             elif test_result.status == "Skipped":
                 print("%s%s%s skipped" %
                       (BOLD[1], test_result.name, BOLD[0]))
             else:
                 print("%s%s%s failed, Duration: %s s\n" %
                       (BOLD[1], test_result.name, BOLD[0], test_result.time))
                 print(BOLD[1] + 'stdout:' + BOLD[0])
                 print(test_result.stdout)
                 print(BOLD[1] + 'stderr:' + BOLD[0])
                 print(test_result.stderr)
             return
 
         assert False, "we should not be here"
 
     def handle_update_messages():
         """
         handle_update_messages waits for messages to be sent from handle_test_cases via the
         update_queue.  It serializes the results so we can print nice status update messages.
         """
         printed_status = False
         running_jobs = set()
 
         while True:
             message = None
             try:
                 message = update_queue.get(True, poll_timeout)
                 if message is None:
                     break
 
                 # We printed a status message, need to kick to the next line
                 # before printing more.
                 if printed_status:
                     print()
                     printed_status = False
 
                 handle_message(message, running_jobs)
                 update_queue.task_done()
             except Empty as e:
                 if not on_ci():
                     print("Running jobs: {}".format(", ".join(running_jobs)), end="\r")
                     sys.stdout.flush()
                     printed_status = True
 
     def handle_test_cases():
         """
         job_runner represents a single thread that is part of a worker pool.  
         It waits for a test, then executes that test. 
         It also reports start and result messages to handle_update_messages
         """
         while True:
             test = job_queue.get()
             if test is None:
                 break
             # Signal that the test is starting to inform the poor waiting
             # programmer
             update_queue.put(test)
             result = test.run(portseed_offset)
             update_queue.put(result)
             job_queue.task_done()
 
     ##
     # Setup our threads, and start sending tasks
     ##
 
     # Start our result collection thread.
     t = threading.Thread(target=handle_update_messages)
     t.setDaemon(True)
     t.start()
 
     # Start some worker threads
     for j in range(num_jobs):
         t = threading.Thread(target=handle_test_cases)
         t.setDaemon(True)
         t.start()
 
     # Push all our test cases into the job queue.
     for i, t in enumerate(test_list):
         job_queue.put(TestCase(i, t, tests_dir, tmpdir, flags))
 
     # Wait for all the jobs to be completed
     job_queue.join()
 
     # Wait for all the results to be compiled
     update_queue.join()
 
     # Flush our queues so the threads exit
     update_queue.put(None)
     for j in range(num_jobs):
         job_queue.put(None)
 
     return test_results
 
 
 def print_results(test_results, max_len_name, runtime):
     results = "\n" + BOLD[1] + "%s | %s | %s\n\n" % (
         "TEST".ljust(max_len_name), "STATUS   ", "DURATION") + BOLD[0]
 
     test_results.sort(key=lambda result: result.name.lower())
     all_passed = True
     time_sum = 0
 
     for test_result in test_results:
         all_passed = all_passed and test_result.was_successful
         time_sum += test_result.time
         test_result.padding = max_len_name
         results += str(test_result)
 
     status = TICK + "Passed" if all_passed else CROSS + "Failed"
     results += BOLD[1] + "\n%s | %s | %s s (accumulated) \n" % (
         "ALL".ljust(max_len_name), status.ljust(9), time_sum) + BOLD[0]
     results += "Runtime: %s s\n" % (runtime)
     print(results)
 
 
 class TestResult():
     """
     Simple data structure to store test result values and print them properly
     """
 
     def __init__(self, name, status, time, stdout, stderr):
         self.name = name
         self.status = status
         self.time = time
         self.padding = 0
         self.stdout = stdout
         self.stderr = stderr
 
     def __repr__(self):
         if self.status == "Passed":
             color = BLUE
             glyph = TICK
         elif self.status == "Failed":
             color = RED
             glyph = CROSS
         elif self.status == "Skipped":
             color = GREY
             glyph = CIRCLE
 
         return color[1] + "%s | %s%s | %s s\n" % (self.name.ljust(self.padding), glyph, self.status.ljust(7), self.time) + color[0]
 
     @property
     def was_successful(self):
         return self.status != "Failed"
 
 
 def get_all_scripts_from_disk(test_dir, non_scripts):
     """
     Return all available test script from script directory (excluding NON_SCRIPTS)
     """
     python_files = set([t for t in os.listdir(test_dir) if t[-3:] == ".py"])
     return list(python_files - set(non_scripts))
 
 
 def get_tests_to_run(test_list, test_params, cutoff, src_timings, build_timings=None):
     """
     Returns only test that will not run longer that cutoff.
     Long running tests are returned first to favor running tests in parallel
     Timings from build directory override those from src directory
     """
 
     def get_test_time(test):
         if build_timings is not None:
             timing = next(
                 (x['time'] for x in build_timings.existing_timings if x['name'] == test), None)
             if timing is not None:
                 return timing
 
         # try source directory. Return 0 if test is unknown to always run it
         return next(
             (x['time'] for x in src_timings.existing_timings if x['name'] == test), 0)
 
     # Some tests must also be run with additional parameters. Add them to the list.
     tests_with_params = []
     for test_name in test_list:
         # always execute a test without parameters
         tests_with_params.append(test_name)
         params = test_params.get(test_name)
         if params is not None:
             tests_with_params.extend(
                 [test_name + " " + " ".join(p) for p in params])
 
     result = [t for t in tests_with_params if get_test_time(t) <= cutoff]
     result.sort(key=lambda x:  (-get_test_time(x), x))
     return result
 
 
 class RPCCoverage():
     """
     Coverage reporting utilities for test_runner.
 
     Coverage calculation works by having each test script subprocess write
     coverage files into a particular directory. These files contain the RPC
     commands invoked during testing, as well as a complete listing of RPC
     commands per `bitcoin-cli help` (`rpc_interface.txt`).
 
     After all tests complete, the commands run are combined and diff'd against
     the complete list to calculate uncovered RPC commands.
 
     See also: test/functional/test_framework/coverage.py
 
     """
 
     def __init__(self):
         self.dir = tempfile.mkdtemp(prefix="coverage")
         self.flag = '--coveragedir={}'.format(self.dir)
 
     def report_rpc_coverage(self):
         """
         Print out RPC commands that were unexercised by tests.
 
         """
         uncovered = self._get_uncovered_rpc_commands()
 
         if uncovered:
             print("Uncovered RPC commands:")
             print("".join(("  - {}\n".format(i)) for i in sorted(uncovered)))
         else:
             print("All RPC commands covered.")
 
     def cleanup(self):
         return shutil.rmtree(self.dir)
 
     def _get_uncovered_rpc_commands(self):
         """
         Return a set of currently untested RPC commands.
 
         """
         # This is shared from `test/functional/test-framework/coverage.py`
         reference_filename = 'rpc_interface.txt'
         coverage_file_prefix = 'coverage.'
 
         coverage_ref_filename = os.path.join(self.dir, reference_filename)
         coverage_filenames = set()
         all_cmds = set()
         covered_cmds = set()
 
         if not os.path.isfile(coverage_ref_filename):
             raise RuntimeError("No coverage reference found")
 
         with open(coverage_ref_filename, 'r') as f:
             all_cmds.update([i.strip() for i in f.readlines()])
 
         for root, dirs, files in os.walk(self.dir):
             for filename in files:
                 if filename.startswith(coverage_file_prefix):
                     coverage_filenames.add(os.path.join(root, filename))
 
         for filename in coverage_filenames:
             with open(filename, 'r') as f:
                 covered_cmds.update([i.strip() for i in f.readlines()])
 
         return all_cmds - covered_cmds
 
 
 def save_results_as_junit(test_results, file_name, time):
     """
     Save tests results to file in JUnit format
 
     See http://llg.cubic.org/docs/junit/ for specification of format
     """
     e_test_suite = ET.Element("testsuite",
                               {"name": "bitcoin_abc_tests",
                                "tests": str(len(test_results)),
                                # "errors":
                                "failures": str(len([t for t in test_results if t.status == "Failed"])),
                                "id": "0",
                                "skipped": str(len([t for t in test_results if t.status == "Skipped"])),
                                "time": str(time),
                                "timestamp": datetime.datetime.now().isoformat('T')
                                })
 
     for test_result in test_results:
         e_test_case = ET.SubElement(e_test_suite, "testcase",
                                     {"name": test_result.name,
                                      "classname": test_result.name,
                                      "time": str(test_result.time)
                                      }
                                     )
         if test_result.status == "Skipped":
             ET.SubElement(e_test_case, "skipped")
         elif test_result.status == "Failed":
             ET.SubElement(e_test_case, "failure")
         # no special element for passed tests
 
         ET.SubElement(e_test_case, "system-out").text = test_result.stdout
         ET.SubElement(e_test_case, "system-err").text = test_result.stderr
 
     ET.ElementTree(e_test_suite).write(
         file_name, "UTF-8", xml_declaration=True)
 
 
 class Timings():
     """
     Takes care of loading, merging and saving tests execution times.
     """
 
     def __init__(self, timing_file):
         self.timing_file = timing_file
         self.existing_timings = self.load_timings()
 
     def load_timings(self):
         if os.path.isfile(self.timing_file):
             with open(self.timing_file) as f:
                 return json.load(f)
         else:
             return []
 
     def get_merged_timings(self, new_timings):
         """
         Return new list containing existing timings updated with new timings
         Tests that do not exists are not removed
         """
 
         key = 'name'
         merged = {}
         for item in self.existing_timings + new_timings:
             if item[key] in merged:
                 merged[item[key]].update(item)
             else:
                 merged[item[key]] = item
 
         # Sort the result to preserve test ordering in file
         merged = list(merged.values())
         merged.sort(key=lambda t, key=key: t[key])
         return merged
 
     def save_timings(self, test_results):
         # we only save test that have passed - timings for failed test might be
         # wrong (timeouts or early fails)
         passed_results = [t for t in test_results if t.status == 'Passed']
         new_timings = list(map(lambda t: {'name':  t.name, 'time': t.time},
                                passed_results))
         merged_timings = self.get_merged_timings(new_timings)
 
         with open(self.timing_file, 'w') as f:
             json.dump(merged_timings, f, indent=True)
 
 
 if __name__ == '__main__':
     main()