import random
s = ‘‘
for i in range(6):
num = random.randint(0,9)
alpha1 = chr(random.randint(65,90))
alpha2 = chr(random.randint(97,122))
ret = random.choice([num,alpha1,alpha2])
s += str(ret)
print(s)
原文：https://www.cnblogs.com/JentZhang/p/11474908.html