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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 _get_alternates(self):
 """The list of alternates for this repo from which objects can be retrieved :return: list of strings being pathnames of alternates"""

        alternates_path = osp.join(self.git_dir, 'objects', 'info', 'alternates')

        if osp.exists(alternates_path):
            with open(alternates_path, 'rb') as f:
                alts = f.read().decode(defenc)
            return alts.strip().splitlines()
        else:
            return []