Update python example to use PyJWT (#33797)

Co-authored-by: Motaz <m-balghonaim@github.com>
Co-authored-by: Alex Nguyen <150945400+nguyenalex836@users.noreply.github.com>

content/apps/creating-github-apps/authenticating-with-a-github-app/generating-a-json-web-token-jwt-for-a-github-app.md

@@ -84,15 +84,16 @@ puts jwt
 
 {% note %}
 
-**Note:** You must run `pip install jwt` to install the `jwt` package in order to use this script.
+**Note:** You must run `pip install PyJWT` to install the `PyJWT` package in order to use this script.
 
 {% endnote %}
 
 ```python copy
 #!/usr/bin/env python3
-from jwt import JWT, jwk_from_pem
-import time
 import sys
+import time
+
+import jwt
 
 
 # Get PEM file path
@@ -117,7 +118,7 @@ else:
 
 # Open PEM
 with open(pem, 'rb') as pem_file:
-    signing_key = jwk_from_pem(pem_file.read())
+    signing_key = pem_file.read()
 
 payload = {
     # Issued at time
@@ -132,8 +133,7 @@ payload = {
 }
 
 # Create JWT
-jwt_instance = JWT()
-encoded_jwt = jwt_instance.encode(payload, signing_key, alg='RS256')
+encoded_jwt = jwt.encode(payload, signing_key, algorithm='RS256')
 
 print(f"JWT:  {encoded_jwt}")
 ```