{"ast_node_type":"import","tokens":[{"end":89,"kind":"keyword","start":0,"text":"//"}]}
                // coroutine. To do so, we use the `CoroutineClosureSignature` to compute
                // for type checking the inner body of the closure, which always returns a
                // the coroutine type, filling in the tupled_upvars_ty and kind_ty with infer