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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 _parse_tag(self, name):
 """Parse a tag command."""

        from_ = self._get_from(b'tag')
        tagger = self._get_user_info(b'tag', b'tagger',
                accept_just_who=True)
        message = self._get_data(b'tag', b'message')
        return commands.TagCommand(name, from_, tagger, message)