Update app.py

app.py

@@ -77,7 +77,11 @@ class OpenAI:
         
         content = result["choices"][0]["message"]["content"].strip()
         
-        visualize_prompt = content.split("### Prompt for Visual Expression\n\n")[1]
+        split_content = content.split("### Prompt for Visual Expression\n\n")
+            if len(split_content) > 1:
+                visualize_prompt = split_content[1]
+            else:
+                visualize_prompt = None  # or any default value
 
         #print("split_content:"+split_content)