fixing the problem with class AsyncResult when using self._is_ready.wait() in wait function

[achrafka]

in this pull request i did this:

1- instead of using Threading and the inbuilt method is_set() which it caused problems i used False and only self._is_ready

[wumb0]

This undoes my fix from #455
Edit: I see what you did, you removed the Event stuff in the first commit and then added it back in your second.
Confusing, but it should be fine.

[achrafka]

Yeah in the second place i did more investigation and i found out that the problem is in the function wait()