diff --git a/test/functional/feature_abortnode.py b/test/functional/feature_abortnode.py
--- a/test/functional/feature_abortnode.py
+++ b/test/functional/feature_abortnode.py
@@ -10,10 +10,11 @@
 - Verify that bitcoind AbortNode's.
 """
 
-from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import get_datadir_path, connect_nodes
 import os
 
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import connect_nodes, get_datadir_path
+
 
 class AbortNodeTest(BitcoinTestFramework):
 
diff --git a/test/functional/feature_assumevalid.py b/test/functional/feature_assumevalid.py
--- a/test/functional/feature_assumevalid.py
+++ b/test/functional/feature_assumevalid.py
@@ -31,7 +31,7 @@
 """
 import time
 
-from test_framework.blocktools import (create_block, create_coinbase)
+from test_framework.blocktools import create_block, create_coinbase
 from test_framework.key import ECKey
 from test_framework.messages import (
     CBlockHeader,
@@ -43,7 +43,7 @@
     msg_headers,
 )
 from test_framework.p2p import P2PInterface
-from test_framework.script import (CScript, OP_TRUE)
+from test_framework.script import OP_TRUE, CScript
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.txtools import pad_tx
 from test_framework.util import assert_equal
diff --git a/test/functional/feature_bip68_sequence.py b/test/functional/feature_bip68_sequence.py
--- a/test/functional/feature_bip68_sequence.py
+++ b/test/functional/feature_bip68_sequence.py
@@ -6,10 +6,7 @@
 
 import time
 
-from test_framework.blocktools import (
-    create_block,
-    create_coinbase,
-)
+from test_framework.blocktools import create_block, create_coinbase
 from test_framework.messages import (
     XEC,
     COutPoint,
diff --git a/test/functional/feature_block.py b/test/functional/feature_block.py
--- a/test/functional/feature_block.py
+++ b/test/functional/feature_block.py
@@ -8,6 +8,7 @@
 import struct
 import time
 
+from data import invalid_txs
 from test_framework.blocktools import (
     create_block,
     create_coinbase,
@@ -17,8 +18,8 @@
 from test_framework.cdefs import LEGACY_MAX_BLOCK_SIZE
 from test_framework.key import ECKey
 from test_framework.messages import (
-    CBlock,
     COIN,
+    CBlock,
     COutPoint,
     CTransaction,
     CTxIn,
@@ -28,7 +29,6 @@
 )
 from test_framework.p2p import P2PDataStore
 from test_framework.script import (
-    CScript,
     OP_ELSE,
     OP_ENDIF,
     OP_FALSE,
@@ -38,14 +38,13 @@
     OP_TRUE,
     SIGHASH_ALL,
     SIGHASH_FORKID,
+    CScript,
     SignatureHashForkId,
 )
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.txtools import pad_tx
 from test_framework.util import assert_equal
 
-from data import invalid_txs
-
 #  Use this class for tests that require behavior other than normal p2p behavior.
 #  For now, it is used to serialize a bloated varint (b64).
 
diff --git a/test/functional/feature_blocksdir.py b/test/functional/feature_blocksdir.py
--- a/test/functional/feature_blocksdir.py
+++ b/test/functional/feature_blocksdir.py
@@ -8,7 +8,10 @@
 import os
 import shutil
 
-from test_framework.test_framework import BitcoinTestFramework, initialize_datadir
+from test_framework.test_framework import (
+    BitcoinTestFramework,
+    initialize_datadir,
+)
 
 
 class BlocksdirTest(BitcoinTestFramework):
diff --git a/test/functional/feature_cltv.py b/test/functional/feature_cltv.py
--- a/test/functional/feature_cltv.py
+++ b/test/functional/feature_cltv.py
@@ -8,24 +8,27 @@
 1351.
 """
 
-from test_framework.blocktools import create_block, create_coinbase, create_transaction, make_conform_to_ctor
+from test_framework.blocktools import (
+    create_block,
+    create_coinbase,
+    create_transaction,
+    make_conform_to_ctor,
+)
 from test_framework.messages import (
     CTransaction,
     FromHex,
+    ToHex,
     msg_block,
     msg_tx,
-    ToHex,
-)
-from test_framework.p2p import (
-    P2PInterface,
 )
+from test_framework.p2p import P2PInterface
 from test_framework.script import (
-    CScript,
-    CScriptNum,
     OP_1NEGATE,
     OP_CHECKLOCKTIMEVERIFY,
     OP_DROP,
     OP_TRUE,
+    CScript,
+    CScriptNum,
 )
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.txtools import pad_tx
diff --git a/test/functional/feature_csv_activation.py b/test/functional/feature_csv_activation.py
--- a/test/functional/feature_csv_activation.py
+++ b/test/functional/feature_csv_activation.py
@@ -40,9 +40,9 @@
 bip112tx_special - test negative argument to OP_CSV
 """
 
+import time
 from decimal import Decimal
 from itertools import product
-import time
 
 from test_framework.blocktools import (
     create_block,
@@ -52,10 +52,10 @@
 from test_framework.messages import XEC, CTransaction, FromHex, ToHex
 from test_framework.p2p import P2PDataStore
 from test_framework.script import (
-    CScript,
     OP_CHECKSEQUENCEVERIFY,
     OP_DROP,
     OP_TRUE,
+    CScript,
 )
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.txtools import pad_tx
diff --git a/test/functional/feature_dbcrash.py b/test/functional/feature_dbcrash.py
--- a/test/functional/feature_dbcrash.py
+++ b/test/functional/feature_dbcrash.py
@@ -41,10 +41,7 @@
     ToHex,
 )
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import (
-    assert_equal,
-    hex_str_to_bytes,
-)
+from test_framework.util import assert_equal, hex_str_to_bytes
 
 
 class ChainstateWriteCrashTest(BitcoinTestFramework):
diff --git a/test/functional/feature_dersig.py b/test/functional/feature_dersig.py
--- a/test/functional/feature_dersig.py
+++ b/test/functional/feature_dersig.py
@@ -7,7 +7,11 @@
 Test that the DERSIG soft-fork activates at (regtest) height 1251.
 """
 
-from test_framework.blocktools import create_block, create_coinbase, create_transaction
+from test_framework.blocktools import (
+    create_block,
+    create_coinbase,
+    create_transaction,
+)
 from test_framework.messages import msg_block
 from test_framework.p2p import P2PInterface
 from test_framework.script import CScript
diff --git a/test/functional/feature_maxuploadtarget.py b/test/functional/feature_maxuploadtarget.py
--- a/test/functional/feature_maxuploadtarget.py
+++ b/test/functional/feature_maxuploadtarget.py
@@ -11,12 +11,12 @@
 * Verify that the upload counters are reset after 24 hours.
 """
 
-from collections import defaultdict
 import time
+from collections import defaultdict
 
-from test_framework.cdefs import LEGACY_MAX_BLOCK_SIZE
 from test_framework.blocktools import mine_big_block
-from test_framework.messages import CInv, MSG_BLOCK, msg_getdata
+from test_framework.cdefs import LEGACY_MAX_BLOCK_SIZE
+from test_framework.messages import MSG_BLOCK, CInv, msg_getdata
 from test_framework.p2p import P2PInterface
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import assert_equal
diff --git a/test/functional/feature_proxy.py b/test/functional/feature_proxy.py
--- a/test/functional/feature_proxy.py
+++ b/test/functional/feature_proxy.py
@@ -38,11 +38,7 @@
     Socks5Server,
 )
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import (
-    assert_equal,
-    PORT_MIN,
-    PORT_RANGE,
-)
+from test_framework.util import PORT_MIN, PORT_RANGE, assert_equal
 
 RANGE_BEGIN = PORT_MIN + 2 * PORT_RANGE  # Start after p2p and rpc ports
 
diff --git a/test/functional/feature_pruning.py b/test/functional/feature_pruning.py
--- a/test/functional/feature_pruning.py
+++ b/test/functional/feature_pruning.py
@@ -13,7 +13,7 @@
 
 from test_framework.blocktools import create_coinbase
 from test_framework.messages import CBlock, ToHex
-from test_framework.script import CScript, OP_RETURN, OP_NOP
+from test_framework.script import OP_NOP, OP_RETURN, CScript
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,
diff --git a/test/functional/feature_settings.py b/test/functional/feature_settings.py
--- a/test/functional/feature_settings.py
+++ b/test/functional/feature_settings.py
@@ -5,7 +5,6 @@
 """Test various command line arguments and configuration file parameters."""
 
 import json
-
 from pathlib import Path
 
 from test_framework.test_framework import BitcoinTestFramework
diff --git a/test/functional/feature_shutdown.py b/test/functional/feature_shutdown.py
--- a/test/functional/feature_shutdown.py
+++ b/test/functional/feature_shutdown.py
@@ -4,9 +4,10 @@
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Test bitcoind shutdown."""
 
+from threading import Thread
+
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import assert_equal, get_rpc_proxy
-from threading import Thread
 
 
 def test_long_call(node):