Function python_global_binding_is_untouched_bounded 

pub fn python_global_binding_is_untouched_bounded(
    name: &str,
    reference: Node<'_>,
    global_scope: Node<'_>,
    source: &str,
    scope_step: impl FnMut() -> bool,
) -> Option<bool>

Prove that a selected global route has no known binding event in its executing enclosing scopes. Outer locals are unrelated to this namespace; an outer scope declaring the same global can still replace its identity. Class namespaces are not captured: only explicit global events are read. The caller has already selected global_scope by lexical precedence.