ValueError: Could not deserialize key data, как решить?

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import random
import binascii
import rsa.randnum
from Crypto.Cipher import Salsa20
from cryptography.fernet import Fernet, MultiFernet
import base64
import qrcode
import image
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.primitives.asymmetric import rsa
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives.asymmetric import rsa
from authlib.specs.rfc7519 import jwt


#cypherText = str.encode(input('Enter text to encrypt: '))



private_key = rsa.generate_private_key(
     public_exponent=65537,
     key_size=2048,
     backend=default_backend()
 )
with open("C:\\LinderChat\\key.pem", "rb") as key_file:
     private_key = serialization.load_pem_private_key(
         key_file.read(),
         password=None,
         backend=default_backend()
     )


#Generate our key
#pubkey = Fernet.generate_key()
#privkey = Fernet.generate_key()
#f = Fernet(privkey)
#fernetText = f.encrypt(cypherText)
#decryptText = f.decrypt(fernetText, ttl = 86400)
#print(fernetText)
#print(privkey)

Ошибка

ValueError: Could not deserialize key data

Подскажите как решить?

Traceback (most recent call last):
  File "c:/Users/AAA/Desktop/Все папки в 1/Программирование/LinderChat.py", line 35, in <module>
    private_key = serialization.load_pem_private_key(
  File "C:\Users\AAA\AppData\Local\Programs\Python\Python38-32\lib\site-packages\cryptography\hazmat\primitives\serialization\base.py", line 16, in load_pem_private_key
    return backend.load_pem_private_key(data, password)
  File "C:\Users\AAA\AppData\Local\Programs\Python\Python38-32\lib\site-packages\cryptography\hazmat\backends\openssl\backend.py", line 1085, in load_pem_private_key
    return self._load_key(
  File "C:\Users\AAA\AppData\Local\Programs\Python\Python38-32\lib\site-packages\cryptography\hazmat\backends\openssl\backend.py", line 1315, in _load_key
    self._handle_key_loading_error()
  File "C:\Users\AAA\AppData\Local\Programs\Python\Python38-32\lib\site-packages\cryptography\hazmat\backends\openssl\backend.py", line 1373, in _handle_key_loading_error
    raise ValueError("Could not deserialize key data.")
ValueError: Could not deserialize key data.