confirm transaction => block hash is non zero

pyhmy/transaction.py

@@ -435,6 +435,7 @@ def send_and_confirm_raw_transaction(signed_tx, endpoint=_default_endpoint, time
     while((time.time() - start_time) <= timeout):
         tx_response = get_transaction_by_hash(tx_hash)
         if tx_response is not None:
+            if tx_response[ 'blockHash' ] != '0x0000000000000000000000000000000000000000000000000000000000000000':
                 return tx_response
         time.sleep(random.uniform(0.2, 0.5))
     raise TxConfirmationTimedoutError("Could not confirm transactions on-chain.")