diff --git a/test/functional/test_framework/script_util.py b/test/functional/test_framework/script_util.py
index 5d1d7ea45c..e0dfce4c2f 100755
--- a/test/functional/test_framework/script_util.py
+++ b/test/functional/test_framework/script_util.py
@@ -3,7 +3,17 @@
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Useful Script constants and utils."""
-from test_framework.script import CScript, hash160, sha256, OP_0, OP_DUP, OP_HASH160, OP_CHECKSIG, OP_EQUAL, OP_EQUALVERIFY
+from test_framework.script import (
+    CScript,
+    hash160,
+    sha256,
+    OP_0,
+    OP_DUP,
+    OP_HASH160,
+    OP_CHECKSIG,
+    OP_EQUAL,
+    OP_EQUALVERIFY,
+)
 
 # To prevent a "tx-size-small" policy rule error, a transaction has to have a
 # non-witness size of at least 82 bytes (MIN_STANDARD_TX_NONWITNESS_SIZE in
@@ -25,28 +35,34 @@ from test_framework.script import CScript, hash160, sha256, OP_0, OP_DUP, OP_HAS
 DUMMY_P2WPKH_SCRIPT = CScript([b'a' * 21])
 DUMMY_2_P2WPKH_SCRIPT = CScript([b'b' * 21])
 
-def keyhash_to_p2pkh_script(hash, main = False):
+
+def keyhash_to_p2pkh_script(hash):
     assert len(hash) == 20
     return CScript([OP_DUP, OP_HASH160, hash, OP_EQUALVERIFY, OP_CHECKSIG])
 
-def scripthash_to_p2sh_script(hash, main = False):
+
+def scripthash_to_p2sh_script(hash):
     assert len(hash) == 20
     return CScript([OP_HASH160, hash, OP_EQUAL])
 
-def key_to_p2pkh_script(key, main = False):
+
+def key_to_p2pkh_script(key):
     key = check_key(key)
-    return keyhash_to_p2pkh_script(hash160(key), main)
+    return keyhash_to_p2pkh_script(hash160(key))
 
-def script_to_p2sh_script(script, main = False):
+
+def script_to_p2sh_script(script):
     script = check_script(script)
-    return scripthash_to_p2sh_script(hash160(script), main)
+    return scripthash_to_p2sh_script(hash160(script))
 
-def key_to_p2sh_p2wpkh_script(key, main = False):
+
+def key_to_p2sh_p2wpkh_script(key):
     key = check_key(key)
     p2shscript = CScript([OP_0, hash160(key)])
-    return script_to_p2sh_script(p2shscript, main)
+    return script_to_p2sh_script(p2shscript)
 
-def program_to_witness_script(version, program, main = False):
+
+def program_to_witness_script(version, program):
     if isinstance(program, str):
         program = bytes.fromhex(program)
     assert 0 <= version <= 16
@@ -54,29 +70,34 @@ def program_to_witness_script(version, program, main = False):
     assert version > 0 or len(program) in [20, 32]
     return CScript([version, program])
 
-def script_to_p2wsh_script(script, main = False):
+
+def script_to_p2wsh_script(script):
     script = check_script(script)
-    return program_to_witness_script(0, sha256(script), main)
+    return program_to_witness_script(0, sha256(script))
 
-def key_to_p2wpkh_script(key, main = False):
+
+def key_to_p2wpkh_script(key):
     key = check_key(key)
-    return program_to_witness_script(0, hash160(key), main)
+    return program_to_witness_script(0, hash160(key))
 
-def script_to_p2sh_p2wsh_script(script, main = False):
+
+def script_to_p2sh_p2wsh_script(script):
     script = check_script(script)
     p2shscript = CScript([OP_0, sha256(script)])
-    return script_to_p2sh_script(p2shscript, main)
+    return script_to_p2sh_script(p2shscript)
+
 
 def check_key(key):
     if isinstance(key, str):
-        key = bytes.fromhex(key) # Assuming this is hex string
+        key = bytes.fromhex(key)  # Assuming this is hex string
     if isinstance(key, bytes) and (len(key) == 33 or len(key) == 65):
         return key
     assert False
 
+
 def check_script(script):
     if isinstance(script, str):
-        script = bytes.fromhex(script) # Assuming this is hex string
+        script = bytes.fromhex(script)  # Assuming this is hex string
     if isinstance(script, bytes) or isinstance(script, CScript):
         return script
     assert False