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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 _git_repo_path(self):
 """ Attempt to determine whether this package is installed via git or not; if so, return the path to the git repository. :rtype: str :returns: path to git repo, or None """

        logger.debug('Checking for git directory in: %s', self._package_top_dir)
        for p in self._package_top_dir:
            gitdir = os.path.join(p, '.git')
            if os.path.exists(gitdir):
                logger.debug('_is_git_clone() true based on %s' % gitdir)
                return gitdir
        logger.debug('_is_git_clone() false')
        return None