{"ast_node_type":"variable","tokens":[{"end":66,"kind":"keyword","start":0,"text":"let"}]}
    let l_curly_token = ctx.find_token_syntax_at_offset(T!['{'])?;
    let assist_label = "Unwrap block";
    let mut block = ast::BlockExpr::cast(l_curly_token.parent_ancestors().nth(1)?)?;