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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:
 def update_room(room):
 """Updates a MUC room on the XMPP server."""


    if room.custom_server:
        return

    def _update_room(xmpp):
        muc = xmpp.plugin['xep_0045']
        muc.joinMUC(room.jid, xmpp.requested_jid.user)
        muc.configureRoom(room.jid, _set_form_values(xmpp, room, muc.getRoomConfig(room.jid)))

    current_plugin.logger.info('Updating room %s', room.jid)
    _execute_xmpp(_update_room)