def get_push_tag_event_message(user_name, tag_name, tag_url=None, action='pushed'):
    if tag_url:
        tag_part = TAG_WITH_URL_TEMPLATE.format(tag_name=tag_name, tag_url=tag_url)
    else:
        tag_part = TAG_WITHOUT_URL_TEMPLATE.format(tag_name=tag_name)
    return PUSH_TAGS_MESSAGE_TEMPLATE.format(user_name=user_name, action=action, tag=tag_part)
def get_push_tag_event_message(user_name, tag_name, tag_url=None, action='pushed'):
    if tag_url:
        tag_part = TAG_WITH_URL_TEMPLATE.format(tag_name=tag_name, tag_url=tag_url)
    else:
        tag_part = TAG_WITHOUT_URL_TEMPLATE.format(tag_name=tag_name)
    return PUSH_TAGS_MESSAGE_TEMPLATE.format(user_name=user_name, action=action, tag=tag_part)