Function python_external_class_member_mutation 

pub fn python_external_class_member_mutation(
    root: Node<'_>,
    source: &str,
    class_identities: &[&str],
    member: &str,
    max_nodes: usize,
) -> Option<PythonModuleMemberMutation>

Find writes to one imported external class member in this file.

The class identities are qualified names taken from one exact active model record (including its exact aliases). Import binders turn those identities into local AST paths; source spelling alone never establishes the class. Dynamic setattr names are treated as possible replacement writes.