This method aims at catching the exception of ValueError, detail:
        http://docs.python-requests.org/zh_CN/latest/user/quickstart.html#json

def get_json_response(self):
        """This method aims at catching the exception of ValueError, detail:
        http://docs.python-requests.org/zh_CN/latest/user/quickstart.html#json
        """
        self.json_response = self.get_response().json()
        if self.json_response is not None:
            error_code = self.json_response.get("errcode", None)
            self.call_status = True if error_code == 0 else False
        return self.json_response