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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(self, *tag, **kwtags):
 """Tag a Property instance with metadata dictionary"""

        if not tag:
            pass
        elif len(tag) == 1 and isinstance(tag[0], dict):
            self._meta.update(tag[0])
        else:
            raise TypeError('Tags must be provided as key-word arguments or '
                            'a dictionary')
        self._meta.update(kwtags)
        return self