Update app.py

app.py

@@ -18,6 +18,7 @@ logging.basicConfig(level=logging.DEBUG, format='%(asctime)s - %(levelname)s - %
 try:
     api_key = os.environ['GEMINI_API_KEY']
 except KeyError:
+    print("Duplicate the space and set your own GEMINI_API_KEY to run.")
     raise ValueError("Please set the GEMINI_API_KEY environment variable.")
 client = genai.Client(api_key=api_key)