Better Fix for flask limiter 4.0

cps/main.py

@@ -46,10 +46,11 @@ def main():
     try:
         from .kobo import kobo, get_kobo_activated
         from .kobo_auth import kobo_auth
+        from flask_limiter.util import get_remote_address
         kobo_available = get_kobo_activated()
     except (ImportError, AttributeError):  # Catch also error for not installed flask-WTF (missing csrf decorator)
         kobo_available = False
-        kobo = kobo_auth = None
+        kobo = kobo_auth = get_remote_address = None
 
     try:
         from .oauth_bb import oauth
@@ -76,6 +77,7 @@ def main():
     app.register_blueprint(gdrive)
     app.register_blueprint(editbook)
     if kobo_available:
+        limiter.limit("3/minute", key_func=get_remote_address)(kobo)
         app.register_blueprint(kobo)
         app.register_blueprint(kobo_auth)
     if oauth_available: