code: def eth_getTransactionByBlockHashAndIndex(self, bhash, index=0):
          
          result = yield from self.rpc_call('eth_getTransactionByBlockHashAndIndex',
                                            [bhash, hex(index)])
          # TODO: Update result response
          return result
docs: https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_gettransactionbyblockhashandindex
  
          :param bhash: Block hash
          :type bhash: str
  
          :param index: Index position (optional)
          :type index: int