code: def fetchUnread(self):
          
          form = {
              "folders[0]": "inbox",
              "client": "mercury",
              "last_action_timestamp": now() - 60 * 1000
              # 'last_action_timestamp': 0
          }
          j = self._post(
              self.req_url.UNREAD_THREADS, form, fix_request=True, as_json=True
          )
  
          payload = j["payload"]["unread_thread_fbids"][0]
          return payload["thread_fbids"] + payload["other_user_fbids"]
docs: Get the unread thread list
  
          :return: List of unread thread ids
          :rtype: list
          :raises: FBchatException if request failed