def internal_send_private_message(realm: Realm, sender: UserProfile, recipient_user: UserProfile, content: str) -> Optional[int]:
    message = internal_prep_private_message(realm, sender, recipient_user, content)
    if (message is None):
        return None
    message_ids = do_send_messages([message])
    return message_ids[0]
def internal_send_private_message(realm: Realm, sender: UserProfile, recipient_user: UserProfile, content: str) -> Optional[int]:
    message = internal_prep_private_message(realm, sender, recipient_user, content)
    if (message is None):
        return None
    message_ids = do_send_messages([message])
    return message_ids[0]