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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 is_older_than_metadata(self):
 """ Return True if the package save file is older than the metadata. If it is, it should be rebuilt. Returns False if the time of either can't be determined :param path: Optional extra save path, used in save_path() """


        try:
            path = self.doc_file.path
        except AttributeError:
            path = self.doc_file

        source_ref = self._doc.ref.path

        try:
            age_diff = getmtime(source_ref) - getmtime(path)

            return age_diff > 0

        except (FileNotFoundError, OSError):
            return False