def request_time(self):
        if self._finish_time is None:
            return time.time() - self._start_time
        else:
            return self._finish_time - self._start_time
Check that method name exists in interface and requires no parameters.
dataset/ETHPy150Open D-L/SimpleBookMarks/src/tornado/wsgi.py/HTTPRequest.request_time--crossover with--dataset/ETHPy150Open ClusterHQ/flocker/benchmark/_method.py/validate_no_arg_method