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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def on_raw_004(self, message):
 """ Basic server information. """

        target, hostname, ircd, user_modes, channel_modes = message.params[:5]

        # Set valid channel and user modes.
        self._channel_modes = set(channel_modes)
        self._user_modes = set(user_modes)