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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 _make_subvolume(self, **args):
 """Creates a subvolume, adds it to this class and returns it."""


        from imagemounter.volume import Volume
        v = Volume(disk=self.disk, parent=self.parent,
                   volume_detector=self.volume_detector,
                   **args)  # vstype is not passed down, let it decide for itself.
        self.volumes.append(v)
        return v