diff --git a/contrib/testgen/base58.py b/contrib/testgen/base58.py
--- a/contrib/testgen/base58.py
+++ b/contrib/testgen/base58.py
@@ -119,7 +119,7 @@
 
 if __name__ == '__main__':
     # Test case (from http://gitorious.org/bitcoin/python-base58.git)
-    assert get_bcaddress_version('15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC') is 0
+    assert get_bcaddress_version('15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC') == 0
     _ohai = 'o hai'.encode('ascii')
     _tmp = b58encode(_ohai)
     assert _tmp == 'DYB3oMS'