test: create assert_not_equal util and add to where imports are needed

In the functional tests there are lots of cases where we assert != which
this new util will replace, we also are adding the imports and the new assertion

test/functional/wallet_fundrawtransaction.py

@@ -18,6 +18,7 @@ from test_framework.messages import (
 )
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
+    assert_not_equal,
     assert_approx,
     assert_equal,
     assert_fee_amount,
@@ -660,7 +661,7 @@ class RawTransactionsTest(BitcoinTestFramework):
         outputs = {self.nodes[0].getnewaddress():1.1}
         rawtx = wallet.createrawtransaction(inputs, outputs)
         fundedTx = wallet.fundrawtransaction(rawtx)
-        assert fundedTx["changepos"] != -1
+        assert_not_equal(fundedTx["changepos"], -1)
 
         # Now we need to unlock.
         with WalletUnlock(wallet, "test"):
@@ -903,10 +904,10 @@ class RawTransactionsTest(BitcoinTestFramework):
         for out in res_dec['vout']:
             if out['value'] > 1.0:
                 changeaddress += out['scriptPubKey']['address']
-        assert changeaddress != ""
+        assert_not_equal(changeaddress, "")
         nextaddr = self.nodes[3].getnewaddress()
         # Now the change address key should be removed from the keypool.
-        assert changeaddress != nextaddr
+        assert_not_equal(changeaddress, nextaddr)
 
     def test_option_subtract_fee_from_outputs(self):
         self.log.info("Test fundrawtxn subtractFeeFromOutputs option")