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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 config_name_from_full_name(full_name):
 """Extract the config name from a full resource name. "my-config" :type full_name: str :param full_name: The full resource name of a config. The full resource name looks like ``projects/project-name/configs/config-name`` and is returned as the ``name`` field of a config resource. See https://cloud.google.com/deployment-manager/runtime-configurator/reference/rest/v1beta1/projects.configs :rtype: str :returns: The config's short name, given its full resource name. :raises: :class:`ValueError` if ``full_name`` is not the expected format """

    projects, _, configs, result = full_name.split("/")
    if projects != "projects" or configs != "configs":
        raise ValueError(
            "Unexpected format of resource",
            full_name,
            'Expected "projects/{proj}/configs/{cfg}"',
        )
    return result