{"ast_node_type":"other","tokens":[{"end":38,"kind":"keyword","start":0,"text":"//"}]}
    // item -> ASSOC_ITEM_LIST -> IMPL
    let real_file_item = ctx.sema.original_syntax_node_rooted(&macro_file_item)?;
    let impl_def = ast::Impl::cast(macro_file_item.parent()?.parent()?)?;