Python指定生成N位随机数

import random

def randomNum(N):
    random_number = random.sample('abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789',N)
    return  ''.join(random_number)

print(randomNum(16))
print(randomNum(32))