code: def get_session_list(self, account):
          
          res = self._get(
              'https://api.weixin.qq.com/customservice/kfsession/getsessionlist',
              params={'kf_account': account},
              result_processor=lambda x: x['sessionlist']
          )
          return res
docs: 获取客服的会话列表
          详情请参考
          http://mp.weixin.qq.com/wiki/2/6c20f3e323bdf5986cfcb33cbd3b829a.html
  
          :param account: 完整客服账号
          :return: 客服的会话列表