def METHOD_NAME(self, nested_severity_ruleset):
    rules = SeverityRules._parse_raw_severity_rules(nested_severity_ruleset)
    _ = next(rules), next(rules), next(rules)  # skip first three
    expressions, modifier = next(rules)
    assert expressions == (
        Expression("foo", "0xc0ffee"),
        Expression("bar", "0xbadc0de"),
    ), "could not find a properly parsed compound rule"
    assert callable(modifier)