code: def send_message(contacts, message):
          
          if type(contacts) == str:
              contacts = [contacts]
  
          recipients = list(set(contacts))
  
          send_notification(
              subsystem='UNKNOWN',
              recipients=[NotificationContact('slack', x) for x in recipients],
              subject=None,
              body_html=message,
              body_text=message
          )
docs: List of contacts the send the message to. You can send messages either to channels and private groups by
          using the following formats
  
          #channel-name
          @username-direct-message
  
          If the channel is the name of a private group / channel, you must first invite the bot to the channel to ensure
          it is allowed to send messages to the group.
  
          Returns true if the message was sent, else `False`
  
          Args:
              contacts (:obj:`list` of `str`,`str`): List of contacts
              message (str): Message to send
  
          Returns:
              `bool`