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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 _repo_name(self):
 """ Returns the name of the repository, using the local directory name. :returns: str """


        if self._git_repo_name is not None:
            return self._git_repo_name
        else:
            reponame = self.repo.git_dir.split(os.sep)[-2]
            if reponame.strip() == '':
                return 'unknown_repo'
            return reponame