Update app.py

app.py

@@ -1,7 +1,12 @@
 #try to rebuilt
 import os
 import gradio as gr
-demo = gr.load("giurimatrix/chatbot", src="spaces",api_key=os.environ.get("hf_token_giurimatrix"))
-demo.launch() 
+
+api_key = os.environ.get("hf_token_giurimatrix")
+if api_key is None:
+    raise ValueError("API key non trovata. Configura la variabile d'ambiente hf_token_giurimatrix.")
+
+demo = gr.load("giurimatrix/chatbot", src="spaces", api_key=api_key)
+demo.launch()