سؤال 34

A program runs `a = [[1]]`, `b = a.copy()`, and `b[0].append(2)`. What is `a`?

`[[1, 2]]`پاسخ درست
`[[1]]` because every nested object was copied
`[1, 2]` because the outer level is removed
`None` because copy mutates its receiver

توضیح

The copy has a distinct outer list but retains a reference to the same nested list as `a`. Mutating that inner object is visible through both outer lists, while a recursive copy would have prevented the shared change.

توضیح

ادامهٔ این آزمون