Given a message, directly invoke the lamdba function for this task.

def _send(self, message):
        """
        Given a message, directly invoke the lamdba function for this task.
        """
        message['command'] = 'zappa.asynchronous.route_lambda_task'
        payload = json.dumps(message).encode('utf-8')
        if len(payload) > LAMBDA_ASYNC_PAYLOAD_LIMIT: # pragma: no cover
            raise AsyncException("Payload too large for async Lambda call")
        self.response = self.client.invoke(
                                    FunctionName=self.lambda_function_name,
                                    InvocationType='Event', #makes the call async
                                    Payload=payload
                                )
        self.sent = (self.response.get('StatusCode', 0) == 202)