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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 unregister(self, bucket, name):
 """ Remove the function from the registry by name """

        assert bucket in self, 'Bucket %s is unknown' % bucket
        if not name in self[bucket]:
            raise NotRegistered('The function %s is not registered' % name)
        del self[bucket][name]