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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 _class_tags(cls):
 # pylint: disable=no-self-argument """ Collect the tags from all base classes. """

        class_tags = set()

        for base in cls.mro()[1:]:  # pylint: disable=no-member
            class_tags.update(getattr(base, '_class_tags', set()))

        return class_tags