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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 _get_container_id(self, labels):
 """ Should only be called on a container-scoped metric It gets the container id from the podlist using the metrics labels :param labels :return str or None """

        namespace = CadvisorPrometheusScraperMixin._get_container_label(labels, "namespace")
        pod_name = CadvisorPrometheusScraperMixin._get_container_label(labels, "pod_name")
        container_name = CadvisorPrometheusScraperMixin._get_container_label(labels, "container_name")
        return self.pod_list_utils.get_cid_by_name_tuple((namespace, pod_name, container_name))