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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 _all_filenames(self):
 """Return a list of absolute cache filenames"""

        try:
            return [os.path.join(self.cache_dir, filename) for filename in
                    os.listdir(self.cache_dir)]
        except (FileNotFoundError, OSError):
            return []