python无限生成不重复(字母,数字,字符)组合的方法

import itertools
mylist=(\"\".join(x) for x in itertools.product(\"0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ\",repeat=16))
while True:
  print(next(mylist))

0000000000003MCk
0000000000003MCl
0000000000003MCm
0000000000003MCn
0000000000003MCo
0000000000003MCp
0000000000003MCq
0000000000003MCr
0000000000003MCs
0000000000003MCt
0000000000003MCu
0000000000003MCv
0000000000003MCw
0000000000003MCx
0000000000003MCy
0000000000003MCz
0000000000003MCA
0000000000003MCB
0000000000003MCC