Update app.py

app.py

@@ -866,6 +866,9 @@ def run_gradio_interface():
         Transform your eBooks into immersive audiobooks with optional custom TTS models.
 
         This interface is based on [Ebook2AudioBookXTTS](https://github.com/DrewThomasson/ebook2audiobookXTTS).
+
+        Free Google Colab [![Free Google Colab](https://github.com/user-attachments/assets/a8a0d8c8-d605-4f52-a812-d45c779510a9)](https://colab.research.google.com/github/DrewThomasson/ebook2audiobookXTTS/blob/main/Notebooks/colab_ebook2audiobookxtts.ipynb)
+
         """
         )