Including startup file in each user server on Jupyterhub

I saw how Colab has a welcome file when you start your server. I’d like to include a welcome file as well in my current Jupyterhub setup which is deployed through Kubernetes.

I saw that there was c.Spawner.args = ['--NotebookApp.default_url=/contents/Welcome.ipynb'] but I get an error saying page does not exist, meaning I need to have this welcome file in advance.

I’ve also come across this link which may shed some light on this. Has anyone tried this?
https://zero-to-jupyterhub.readthedocs.io/en/latest/customizing/user-environment.html

You could add it into your notebook image or copy it before spawning in pre_spawn_hook.