You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: default_parameters.rs
    path of file: ./repos/gdext/godot-codegen/src/generator
    
    the code of the file until where you have to start completion: /*
 * Copyright (c) godot-rust; Bromeon and contributors.
 * This Source Code Form is subject 
    
fn make_extender_doc(sig: &dyn Function, extended_fn_name: &Ident) -> (String, TokenStream) {
    // Not in the above match, because this is true for both static/instance methods.
    // Static/instance is determined by first argument (always use fully qualified function call syntax).
    let surround_class_prefix;
    let builder_doc;

    match sig.surrounding_class() {
        Some(TyName { rust_ty, .. }) => {
            surround_class_prefix = quote! { re_export::#rust_ty:: };
            builder_doc = format!(
                "Default-param extender for [`{class}::{method}`][super::{class}::{method}].",
                class = rust_ty,
                method = extended_fn_name,
            );
        }
        None => {
            // There are currently no default parameters for utility functions
            // -> this is currently dead code, but _should_ work if Godot ever adds them.
            surround_class_prefix = TokenStream::new();
            builder_doc = format!(
                "Default-param extender for [`{function}`][super::{function}].",
                function = extended_fn_name
            );
        }
    };

    (builder_doc, surround_class_prefix)
}