code: def json(self, url, method='get', params=None, data=None):
          
          r = self.req(url, method, params, data)
          return r.json()
docs: 请求并返回json
          
          
          :type url: str
          :param url: API
          
          :type method: str
          :param method: HTTP METHOD
          
          :type params: dict
          :param params: query
          
          :type data: dict
          :param data: body
          
          :rtype: dict
          :return: