tests: Use explicit imports

test/functional/feature_rbf.py

@@ -4,10 +4,12 @@
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Test the RBF code."""
 
+from decimal import Decimal
+
+from test_framework.messages import COIN, COutPoint, CTransaction, CTxIn, CTxOut
+from test_framework.script import CScript, OP_DROP
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import *
-from test_framework.script import *
-from test_framework.mininode import *
+from test_framework.util import assert_equal, assert_raises_rpc_error, bytes_to_hex_str, satoshi_round
 
 MAX_REPLACEMENT_LIMIT = 100