docs: def send_message(self, user=None, message=None, channel=None):
      """ Todo """
      self.logger.info("sending message to %s: %s", user, message)
      cid=channel
      if not cid:
        for cid in self.channels:
          if str(self.channels[cid]) == str(user):
            channel=cid
            self.logger.debug(cid)
      if (channel):
        self.post('channels/'+cid+'/messages',
                  json.dumps({'content': message,
                              'nonce': random_integer(-2**63, 2**63 - 1)}))
      else:
        logger.error("Unknown user %s",user)