If I did that, the code would always return at the first GetSession call.

Instead, it unwraps exceptions, and while it propagates cancelations, it ignores other exceptions and tries other providers in turn.

In fact, I could even use `break` or `continue` in the midst of async code, and there would be no problem.

Also I just love using `try` and `finally` in async code—with callbacks, you have to do finalization from all error and success paths (which can be a lot of places).