center(width ,fillchar)
center is a string helper. You call it on text like "Asha" or "banana". It gives a new string (or a number/True-False). The old string does not change unless you assign the result back.
center(width ,fillchar) — output — --Asha--- (width 10).
Fresher trap: writing s.center() and expecting s to update. Strings are immutable. Write s = s.center(...) if you need the new value (when it returns a string).
Exam tip
Call center on one real word and say what prints.