{"ast_node_type":"variable","tokens":[{"end":100,"kind":"keyword","start":0,"text":"let"}]}
        let tokens = node.tokens().unwrap_or_else(|| panic!("missing tokens for node: {:?}", node));
    pub fn from_ast(node: &(impl HasAttrs + HasTokens + fmt::Debug)) -> TokenStream {
        let mut tts = vec![];