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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 delMatch(self, rule_id):
 """ Removes a message matching rule previously registered with addMatch """

        rule = self.match_rules[rule_id]

        d = self.callRemote(
            '/org/freedesktop/DBus',
            'RemoveMatch',
            interface='org.freedesktop.DBus',
            destination='org.freedesktop.DBus',
            body=[rule],
            signature='s',
        )

        def ok(_):
            del self.match_rules[rule_id]
            self.router.delMatch(rule_id)

        d.addCallback(ok)

        return d