{"ast_node_type":"other","tokens":[{"end":63,"kind":"keyword","start":0,"text":"tupled_upvars_ty:"}]}
                tupled_upvars_ty: tupled_upvars_ty.expect_ty(),
                signature_parts_ty: signature_parts_ty.expect_ty(),
                coroutine_captures_by_ref_ty: coroutine_captures_by_ref_ty.expect_ty(),