Python: why does `random.randint(a, b)` return a range inclusive of `b`?

Question

It has always seemed strange to me that random.randint(a, b) would return an integer in the range [a, b], instead of [a, b-1] like

Answer 1

I guess random.randint was just the first attempt at implementing this feature. It seems that the Python developers also felt that this was a problem, which is why in v1.5.2 they added another method randrange with more standard parameters:

random.randrange([start], stop[, step])

Return a randomly selected element from range(start, stop, step). This is equivalent to choice(range(start, stop, step)), but doesn’t actually build a range object.

You can use randrange instead of randint to avoid surprising people.

On the other hand, in many situations where the problem is phrased as 'choose a random number between 1 and 6' it might be more natural to use randint(1, 6) instead of writing randrange(1, 7) or randrange(min, max + 1).