lib.rs

    let ast: syn::ItemFn = syn::parse(input).unwrap();
    let name = ast.ident;
    let block = ast.block;
    let attrs = ast.attrs;
    let gen = quote! {
        #(#attrs)
        *
        fn #name () {
            serial_test::serial_core(#key, || {
                #block
            });
        }
    };
    return gen.into();