[Python] Encode text using base64 and AES

I'm trying to decode data which is generated from this JavaScript code:

jeTV: (t, e, r) => {
"use strict";
r.d(e, {
X: () => s
});
var n = r("wIp5")
, i = r.n(n)
, s = (r("4Whi"),
function(t, e) {
var r = i().lib.WordArray.random(12).toString(i().enc.Base64)
, n = i().AES.encrypt(t, i().enc.Utf8.parse(e), {
iv: i().enc.Utf8.parse(r)
});
return "".concat(r).concat(n.ciphertext.toString(i().enc.Base64))
}
)
}


My code:

def decrypt(encrypted_data, key):
# Extract the Base64 IV and ciphertext
iv_base64 = encrypted_data[:16] # First 16 characters (Base64-encoded IV)
ciphertext_base64 = encrypted_data[16:] # The rest is the ciphertext

# Use the Base64 string directly as IV, without decoding it back to bytes
iv_bytes = iv_base64[:16].encode('utf-8') # Get the first 16 chars of the Base64-encoded IV

# Decode the ciphertext
ciphertext = base64_decode(ciphertext_base64)

# Create AES cipher object for decryption
cipher = AES.new(key.encode('utf-8'), AES.MODE_CBC, iv_bytes)

# Decrypt and unpad the plaintext
plaintext = unpad(cipher.decrypt(ciphertext), AES.block_size)

return plaintext.decode('utf-8')


But I got this error when run the program:

plaintext = unpad(cipher.decrypt(ciphertext), AES.block_size)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "D\venv\Lib\site-packages\Crypto\Util\Padding.py", line 95, in unpad
raise ValueError("PKCS#7 padding is incorrect.")
ValueError: PKCS#7 padding is incorrect.


I checked the key and the Base64-decoded IV/ciphertext, and they seem to match what was generated during encryption. I printed the raw decrypted bytes, but I’m not sure if they are binary data or not. Any insights or suggestions on how to resolve this issue would be appreciated.

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