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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 sub_path(self):
 """The path of the partition source, excluding the bundle path parts. Includes the revision. """


        try:
            return os.path.join(*(self._local_parts()))
        except TypeError as e:
            raise TypeError(
                "Path failed for partition {} : {}".format(
                    self.name,
                    e.message))