[functional test] getprioritisedtransactions RPC

test/functional/mempool_expiry.py

@@ -12,7 +12,10 @@ definable expiry timeout via the '-mempoolexpiry=<n>' command line argument
 
 from datetime import timedelta
 
-from test_framework.messages import DEFAULT_MEMPOOL_EXPIRY_HOURS
+from test_framework.messages import (
+    COIN,
+    DEFAULT_MEMPOOL_EXPIRY_HOURS,
+)
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,