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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: str, overwrite: bool = False) -> None: """ Tags the current commit :param tag: tag :type tag: str :param overwrite: overwrite existing tag :type overwrite: bool """

        LOGGER.info('tagging repo: %s', tag)
        try:
            self.repo.create_tag(tag)
        except GitCommandError as exc:
            if 'already exists' in exc.stderr and overwrite:
                LOGGER.info('overwriting existing tag')
                self.remove_tag(tag)
                self.repo.create_tag(tag)
            else:
                LOGGER.exception('error while tagging repo')
                raise