code: def send(self, message, channel_name=None, fail_silently=False,
               options=None):
          # type: (Text, Optional[str], bool, Optional[SendOptions]) -> None
          
          if channel_name is None:
              channels = self.settings["CHANNELS"]
          else:
              try:
                  channels = {
                      "__selected__": self.settings["CHANNELS"][channel_name]
                  }
              except KeyError:
                  raise Exception("channels does not exist %s", channel_name)
  
          for _, config in channels.items():
              if "_backend" not in config:
                  raise ImproperlyConfigured(
                      "Specify the backend class in the channel configuration")
  
              backend = self._load_backend(config["_backend"])  # type: Any
              config = deepcopy(config)
              del config["_backend"]
              channel = backend(**config)
              channel.send(message, fail_silently=fail_silently, options=options)
docs: Send a notification to channels
  
          :param message: A message