Update app.py

app.py

@@ -6,7 +6,9 @@ import uuid
 def send_post_request(prompt, ratio, style, uuid, token):
     # Define the URL
     
-    url = os.getenv('API_URL')  # Make sure 'API_URL' is the name you used for the public variable
+    url = os.getenv('API_URL')  # Secret variable for the URL
+    if not url:
+        return "Error: API URL not set in environment secrets."
 
 
     # Define the headers with the required values