我们可以存储所有以前生成的字符串，并根据该列表检查任何新字符串，但是在大量运行之后，您可能会用完唯一字符串。

import os
import binascii

generated_hexes = set()

while True:
    new_hex = binascii.hexlify(os.urandom(2)).decode('utf-8')
    if new_hex not in generated_hexes:
        print(new_hex)
        generated_hexes.add(new_hex)

对于这种情况，您需要将代码存储在某个地方，例如Python中的列表。
在此之后，有必要检查新代码是否存在于此列表中。
您可以根据需要修改以下代码。

import os
import binascii

list_codes = []

num = 1

while num == 1:
    hex = binascii.hexlify(os.urandom(2)).decode('utf-8')
    if hex not in list_codes:
      list_codes.append(hex)
      print(hex)
    num = int(input("Press 1 to continue "))

您需要保存您打印的值，并在打印下一个值之前检查它是否已经打印过。

import os
import binascii

previously_printed = []
def print_new_random_hex():
    random_hex = binascii.hexlify(os.urandom(2)).decode('utf-8')
    while random_hex in previously_printed:
        random_hex = binascii.hexlify(os.urandom(2)).decode('utf-8')
    print(random_hex)
    previously_printed.append(random_hex)

为了让计算机记住上一次运行时打印的内容，您需要另一个文件来保存您打印的值。在下面的代码中，文件是previously_printed.txt

import os
import binascii

with open('previously_printed.txt', 'r') as file:
    previously_printed = file.read().split('\n')

with open('previously_printed.txt', 'a') as file:
    random_hex = binascii.hexlify(os.urandom(2)).decode('utf-8')
    while random_hex in previously_printed:
        print("yay we avoided printing", random_hex, "a second time!")
        random_hex = binascii.hexlify(os.urandom(2)).decode('utf-8')

    print(random_hex)
    file.write('\n' + random_hex)