code: async def on_raw_cap(self, message):
          
          target, subcommand = message.params[:2]
          params = message.params[2:]
  
          # Call handler.
          attr = 'on_raw_cap_' + pydle.protocol.identifierify(subcommand)
          if hasattr(self, attr):
              await getattr(self, attr)(params)
          else:
              self.logger.warning('Unknown CAP subcommand sent from server: %s', subcommand)
docs: Handle CAP message.