提供一个编码方式，每次执行得到不同的结果

import base64
import random

# 提供一个编码方式，每次执行得到不同的结果
def s_encode(key,source):
    temp_array = source.encode('utf-8')
    source = base64.b64encode(temp_array).decode('utf-8')
    ch_array = list(source)
    key_chars = list(key)
    num = random.randint(0, 0xff)
    builder = []
    if num > 15:
        builder.append(format(num, 'x'))
    else:
        builder.append('0' + format(num, 'x'))
    num2 = int(''.join(builder), 16)
    for i in range(len(ch_array)):
        if (ord(ch_array[i]) + num2) > 0xff:
            num2 = ((ord(ch_array[i]) + num2) - 0xff) ^ ord(key_chars[i % 13])
        else:
            num2 = (ord(ch_array[i]) + num2) ^ ord(key_chars[i % 13])
        if num2 > 15:
            builder.append(format(num2, 'x'))
        else:
            builder.append('0' + format(num2, 'x'))
    return ''.join(builder).upper()

def s_decode(key,source):
    key_chars = list(key)
    builder = []
    ch_array = list(source)
    for i in range(0, len(ch_array) - 2, 2):
        str1 = ch_array[i + 2] + ch_array[i + 3]
        str2 = format(ord(key_chars[(i // 2) % 13]), 'x')
        str3 = ch_array[i] + ch_array[i + 1]
        num2 = (int(str1, 16) ^ int(str2, 16)) - int(str3, 16)
        if num2 < 0:
            num2 += 0xff
        builder.append(chr(num2))
    decode_str = base64.b64decode(''.join(builder)).decode('utf-8')
    return decode_str

def main():

    #key = 'yA36zA48dEhfrvghGRg57h5UlDv3'
    #key = '0102030405060708091011121314'
    key = 'DE13B1B580436E63DE13B1B58043'
    #source='this is a python sample！'
    source='This is a python coding sample'
    en_source=s_encode(key,source)
    print(f'key[{len(key)}]={key}')
    print(f'source={source}')
    print(f'en_source[{len(en_source)}]={en_source}')
    dec_source=s_decode(key,en_source)
    print(f'dec_source={dec_source}')
    print(f'source==dec_source={source==dec_source}')

if __name__ == '__main__':
    main()