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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 container_instance_from_string(id):
 """Create a ContainerInstance from an id string"""

    try:
        service, instance = id.rsplit('_', 1)
        instance = int(instance)
    except (TypeError, ValueError):
        raise context.ValueError("Invalid container id %r" % id)
    return _proto.ContainerInstance(service_name=service, instance=instance)