syntax_data: {"ast_node_type":"other","tokens":[{"end":68,"kind":"keyword","start":0,"text":"write!(self,"}]}
source_snippet:                     write!(self, " coroutine_captures_by_ref_ty=")?;
context_before:                     args.as_coroutine_closure().tupled_upvars_ty().print(self)?;
context_after:                     args.as_coroutine_closure().coroutine_captures_by_ref_ty().print(self)?;