how can this iterator be optimized?

[Terry Reedy]

Basilisk96 wrote:
>> Don't use a generator then. If you're going to finally return a list (and  
>> sorted does exactly that), build a list right from the start:
> 
> Good point. However, for the sake of argument, what if I removed the
> sorting requirement and simply wanted the generator?

Write a generator function with the same loop and a yield.

? I usually strive
> for comprehensions if a for loop can be reduced to such.

You are overdoing it, I think.  Generator expressions are for saving 
programmer time, not machine time.