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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 tag(tags):
 """Returns a function that adds the words in `tags` as class tags to this class."""

        def dec(cls):
            """Add the words in `tags` as class tags to this class."""
            # Add in this class's tags
            cls._class_tags.update(tags.replace(",", " ").split())  # pylint: disable=protected-access
            return cls
        return dec