[ad_1]
I think this is more of a subjective question. I would argue that its ok following the principle of duck typing: If it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck.
If you are looping through an array of strings and they all have the format() method, then just assume they all have something to be formated and format it.
[ad_2]
solved python string format without {}