Python Repeat Question. It's a bit confusing

a = [i for i in features if i != alphabet]

The above code is translated as follows:

This is what happens when you change the third step of the above translation to obtain i*2.

a = [i*2 for i in features if i != alphabet]

Finally... Why i? Since the iterator is called an iterator in English, it is i after the first letter. That's just why most repetitions in most languages typically use i.