Fix examples loading

app.py

@@ -120,8 +120,8 @@ def generate_podcast(url: str, pdf_path: str, topic: str):
             print(f"PROCESSED '{utterance}' in {int(t1-t0)} seconds. {audio_numpy.shape}")
 
 EXAMPLES = [
-    ["https://huggingface.co/blog/inference-providers-cohere", "", "How does using this compare with other inference solutions?"],
-    ["", str(Path("examples/Essay_Palantir.pdf")), "Make sure to keep some critic spirit in the analysis!"],
+    ["https://huggingface.co/blog/inference-providers-cohere", None, "How does using this compare with other inference solutions?"],
+    [None, str(Path("examples/Essay_Palantir.pdf")), "Make sure to keep some critic spirit in the analysis!"],
 ]
 demo = gr.Interface(
     title="Open NotebookLM 🎙️",