python随机验证码函数

#验证码函数
def yzm(i):
    code = []
    for i in range(i):
        if i == random.randint(1,3):
            code.append(str(random.randint(1,9)))
        else:
            tmp = random.randint(65,90)
            code.append(chr(tmp))
    
    return ''.join(code)