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

    projects, _, configs, _, variables, result = full_name.split("/", 5)
    if projects != "projects" or configs != "configs" or variables != "variables":
        raise ValueError(
            "Unexpected format of resource",
            full_name,
            'Expected "projects/{proj}/configs/{cfg}/variables/..."',
        )
    return result