code: def _load_entities(self):
          
          if not self._chat_peer:
              return True  # Nothing to load (e.g. MessageDeleted)
  
          self._chat, self._input_chat = self._get_entity_pair(self.chat_id)
          return self._input_chat is not None
docs: Must load all the entities it needs from cache, and
          return ``False`` if it could not find all of them.