运行解密响应数据程序：

D:\Python\Python311\python.exe E:\baichuan\youdaos.py

{"code":0,"dictResult":{"ce":{"word":{"trs"D:\Python\Python311\python.exe E:\baichuan\youdaospdm.pyD:\Python\Python311\python.exe E:\baichuan\youdaospdm.py:[{"voice":"hello&type=2","#text":"hello","#tran":"喂，你好（用于问候或打招呼）；喂，你好（打电话时的招呼语）；喂，你好（引起别人注意的招呼语）；<非正式>喂，嘿 (认为别人说了蠢话或分心)；<英，旧>嘿（表示惊讶）；招呼，问候；（Hello）（法、印、美、俄）埃洛（人名）；说（或大声说）“喂”；打招呼；"},{"voice":"hi&type=2","#text":"hi","#tran":"嗨！（表示问候或用以唤起注意）；（Hi）人名；（柬）希；"},{"voice":"how+do+you+do&type=2","#text":"how do you do","#tran":"你好；"}],"phone":"nǐ hǎo","return-phrase":"你好"}}},"translateResult":[[{"tgt":"hello","src":"你好","srcPronounce":"nĭhăo"}]],"type":"zh-CHS2en"}

Process finished with exit code 0
可以看到在末尾多了14个乱码字符，添加了这行代码问题解决了：
a = unpad(a, 16)
原来有道在响应数据中添加了pad，在aes解密后去除pad就好了

import base64
from Crypto.Cipher import AES
from Crypto.Util.Padding import pad, unpad
import hashlib


def decode_data(text):
    decodeiv = "ydsecret://query/iv/C@lZe2YzHtZ2CYgaXKSVfsb7Y4QWHjITPPZ0nQp87fBeJ!Iv6v^6fvi2WN@bYpJ4"
    decodekey = "ydsecret://query/key/B*RGygVywfNBwpmBaZg*WT7SIOUP2T0C9WHMZN39j^DAdaZhAnxvGcCY6VYFwnHl"
    key = hashlib.md5(decodekey.encode(encoding='utf-8')).digest()
    iv = hashlib.md5(decodeiv.encode(encoding='utf-8')).digest()
    # 构造一个AES对象
    aes_en = AES.new(key, AES.MODE_CBC, iv)
    # text是b64编码的数据，将其解码
    data_new = base64.urlsafe_b64decode(text)
    # AES解密数据
    a = aes_en.decrypt(data_new)
    # 去除pad
    a = unpad(a, 16)
    # 解码成str格式
    a = a.decode(encoding='utf-8')
    return a


if __name__ == '__main__':
    s = 'Z21kD9ZK1ke6ugku2ccWu4n6eLnvoDT0YgGi0y3g-v0B9sYqg8L9D6UERNozYOHqnYdl2efZNyM6Trc_xS-zKtfTK4hb6JP8XwCzNh0avc8qItQUiIU_4wKKXJlIpvMvfKvJaaZzaX6VEtpkr2FdkfoT_Jgbm2GRSVj3r40autIdlImENG8hC0ZH4ww7utwuTt3Oo_ZpXg0BSq9wePSAB75-ChkiGKF9HTIPeCl2bl84SBD1XDfFCZpkKQhecYSs0JLoXOqP2ltavxRrg58Hp1q5uIgZZ_Oo2-Jmd-t1r4es40drcAq5bjmS62M2VJF8D6ojtOh9JTfNwgzD3CxYn-Pd7-TgHMyNEJEkFXTAyxzpjlFqtrCYDE3SZUYlENkqsL8Wrra1hM-1n TfiB-BLcWAdRBynNpP5_54aq_-GBsq8bB_9yEX5ovzDB4_Ry_spVVuUnb39iplMHCdCnjOD3ngiIDbl9SUz-9n pjBX05ZYRdPmFPAl424qdoaxeVqnVoH8jQFPZVqaHMzu4mJg0SICDWFH7GP1zqGRbXd3ESjT_iBInl3gICt2XVuhh_nubcELkTEC6xbqEDRQkPUNMpzXJHjcvsLHtcmSW0S9F0445ho9kT2qZYdMBC3Fs0OaHpUtFu77gZpQn7sGiqh8VliXIcUtfvvop-1 c-Vu5QjfUbLn2-s5POR9fGYG6rt6ioe_PGmwWj-Cc00zUM7FybfarKTr4D3Rk57R72qpXN4Ja86ZsCAMmDG-m5z31RQh_V7echJ8Kna3Go3yWKCK4vtSwOWrFhiS5RTz6EkrGc3SkFKbb5vp8Wop_84myBtgnBmj4CczhTq2HcOxrJf4def6yDt2uBxyv4bTVGx9Yx3uB4Gx0iK5kYvfma6B_LnkRWk331wjuXKQtBGYIuWkR8J5QtvBmIRVaa7AA19Z4xMIEAqbcuQ5p4I9FCElthBrJd9YOcouHK4U27xxYWJJXcJoTvzG7zWtiV76fHDeQLgAWvJJ7ww4NFgjhqc6AKA_2afxa4c_lAvVZgFuKL3XSCL7PfKxp6GhjcGKeSRr80PT1gfFw2xi8X4ejjNm_prsUZ'
    res = decode_data(s)
    print(res)