syntax_data: {"ast_node_type":"import","tokens":[{"end":74,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:     // The `RefCell` is used because `<Formatter as Labeller>::node_label`
context_before:     body: &'mir Body<'tcx>,
context_after:     // takes `&self`, but it needs to modify the analysis. This is also the