How to use the hangups.user.UserID function in hangups

def user_id(self):
        """Who created the event (:class:`~hangups.user.UserID`)."""
        return user.UserID(chat_id=self._event.sender_id.chat_id,
                           gaia_id=self._event.sender_id.gaia_id)

conversation will also be retrieved.

    Args:
        client (Client): Connected client.

    Returns:
        (:class:`.UserList`, :class:`.ConversationList`):
            Tuple of built objects.
    """
    conv_states, sync_timestamp = await _sync_all_conversations(client)

    # Retrieve entities participating in all conversations.
    required_user_ids = set()
    for conv_state in conv_states:
        required_user_ids |= {
            user.UserID(chat_id=part.id.chat_id, gaia_id=part.id.gaia_id)
            for part in conv_state.conversation.participant_data
        }
    required_entities = []
    if required_user_ids:
        logger.debug('Need to request additional users: {}'
                     .format(required_user_ids))
        try:
            response = await client.get_entity_by_id(
                hangouts_pb2.GetEntityByIdRequest(
                    request_header=client.get_request_header(),
                    batch_lookup_spec=[
                        hangouts_pb2.EntityLookupSpec(
                            gaia_id=user_id.gaia_id,
                            create_offnetwork_gaia=True,
                        )
                        for user_id in required_user_ids