Fixed all pep8 warnings

controllers/web/endpoints.py

@@ -12,7 +12,7 @@ blueprint.register_blueprint(user.blueprint)
 blueprint.register_blueprint(product.blueprint)
 
 
-### CONTEXTS ###
+# CONTEXTS #
 
 # Function that returns a given user class based on the ID in the session
 @blueprint.context_processor
@@ -21,7 +21,7 @@ def get_user() -> dict[User | None]:
     user_id = session.get('user_id')
     user = None
 
-    if user_id != None:
+    if user_id is not None:
         db = UserController()
         user = db.read_id(user_id)