我建议使用sets和stdlib中的string包作为可接受字符的列表。在

我还建议进行一点重构，以删除大量带有if / else分支的嵌套。在import string

upper = set(list(string.uppercase))

lower = set(list(string.lowercase))

numbers = set(list(string.digits))

while True:

npw = input("Please enter new password: ")

npwc = input("Please confirm new password: ")

if npwc != npw:

print("Passwords don't match")

continue

if len(npcw) < 8:

print("Your password must contain at least 8 characters.")

continue

chars = set(list(npwc))

if not upper.intersection(chars):

print("Your password must contain at least 1 upper case character.")

continue

if not lower.intersection(chars):

print("Your password must contain at least 1 lower case character.")

continue

if not numbers.intersection(chars):

print("Your password must contain a number")

continue

npw = npwc

print("Your password has been changed")

break