LL | let fut = async {
| --- consider giving `fut` the explicit type `impl Future`, with the type parameters specified
LL | make_unit()?;
- | ^ cannot infer type
+ | ^ cannot infer type of error for `?` operator
+ |
+ = note: `?` implicitly converts the error value into a type implementing `From<std::io::Error>`
error: aborting due to previous error; 1 warning emitted