String模块ascii_letters和digits

>>> chars = string.ascii_letters + string.digits
>>> print(chars)
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789

import random, string

def rand_str(num, length=7):
    f = open('Activation_code.txt', 'w')
    for i in range(num):
        chars = string.ascii_letters + string.digits
        s = [random.choice(chars) for i in range(length)]
        f.write('{0}
'.format(''.join(s)))
    f.close()
 
 
if __name__ == '__main__':
    rand_str(200)

wz0dajI
25vlulV
zLHkx9Y
GGzu0Ip
RilbYKW
4WZL2IC
4syobYw
kCMky7O
oUPde55
KrMRmUX
Ct0W2Pm
wMwpPdk
ydPuy9h
Z7vo3r9