import random a=random.randint(0,1001)#这个生成的区间是 [0,1001] a=random.randrange(0,10001)#生成的是区间是[0,1001) print a

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

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

And range(start, stop) returns [start, start+step, ..., stop-1], not [start, start+step, ..., stop]. As for why... zero-based counting rules and range(n) should return n elements, I suppose. Most useful for getting a random index, I suppose.

While randint is documented as:

random.randint(a, b)

Return a random integer N such that a <= N <= b. Alias for randrange(a, b+1)

So randint is for when you have the maximum and minimum value for the random number you want.