Update app.py

app.py

@@ -29,11 +29,11 @@ logging.basicConfig(stream = sys.stdout, level = logging.INFO)
 logging.getLogger().addHandler(logging.StreamHandler(stream = sys.stdout))
 
 def invoke(openai_api_key, prompt, rag_option):
-    if (openai_api_key == ""):
+    if not openai_api_key:
         raise gr.Error("OpenAI API Key is required.")
-    if (prompt == ""):
+    if not prompt:
         raise gr.Error("Prompt is required.")
-    if (rag_option is None):
+    if not rag_option:
         raise gr.Error("Retrieval-Augmented Generation is required.")
 
     with lock: