code: def unread_events(self):
          
          return [conv_event for conv_event in self._events
                  if conv_event.timestamp > self.latest_read_timestamp]
docs: Loaded events which are unread sorted oldest to newest.
  
          Some Hangouts clients don't update the read timestamp for certain event
          types, such as membership changes, so this may return more unread
          events than these clients will show. There's also a delay between
          sending a message and the user's own message being considered read.
  
          (list of :class:`.ConversationEvent`).