Update app.py

app.py

@@ -35,6 +35,9 @@ if process_url_clicked:
     loader = UnstructuredURLLoader(urls=urls)
     main_placeholder.text("Data Loading...Started...✅✅✅")
     data = loader.load()
+    if not data:
+    st.error("Failed to load content from the provided URLs. Please check their availability.")
+    st.stop()
     # split data
     text_splitter = RecursiveCharacterTextSplitter(
         separators=['\n\n', '\n', '.', ','],