Feature summary:

api.APIGenerator should be a Generator as the class name says

Use case(s) :

Currenly all api generators are Iterables; they work with for loops but it doest not support next() function of an Iterator but this is used a couple o times: see here.

This also solves T301318.

Benefits:

Making api generators a collections.abc.Generator they are capable to be used as

• Iterable (for loops etc.)
• Iterator (next() function etc.)
• Generator (close() method which is used by BaseBot; BaseBot tries to convert every Iterable to a Generator)