tests: Use explicit imports

test/functional/mempool_resurrect.py

@@ -4,9 +4,9 @@
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Test resurrection of mined transactions when the blockchain is re-organized."""
 
-from test_framework.test_framework import BitcoinTestFramework
 from test_framework.blocktools import create_raw_transaction
-from test_framework.util import *
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import assert_equal
 
 
 class MempoolCoinbaseTest(BitcoinTestFramework):