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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 _clone(self, cid):
 """ Create a temporary image snapshot from a given cid. Temporary image snapshots are marked with a sentinel label so that they can be cleaned on unmount. """

        try:
            iid = self.client.commit(
                container=cid,
                conf={
                    'Labels': {
                        'io.projectatomic.Temporary': 'true'
                    }
                }
            )['Id']
        except docker.errors.APIError as ex:
            raise MountError(str(ex))
        self.tmp_image = iid
        return self._create_temp_container(iid)