Five functions are created, but all of them just multiply ``x`` by 4.

Python's closures are *late binding*. This means that names within closures are

looked up at the time the inner function is *called*.

Python's closures are *late binding*.

This means that the values of variables used in closures are looked

up at the time the inner function is called.

Here, whenever *any* of the returned functions are called, the value of ``i``

is looked up in the surrounding scope at call time, when bythen the loop has

is looked up in the surrounding scope at call time. Bythen, the loop has

completed and ``i`` is left with its final value of 4.

What's particularly nasty about this gotcha is the seemingly prevalent