/healthz route of an app deployed on Google App Engine returns 404

Question

HTTP requests for a /healthz route on an app deployed on Google App Engine don't seem to reach the /healthz endpoint within the app.
Instead, a 404 page is served, apparently from the GCP infrastructure.
Can I know how to override this behaviour and make these requests reach my app?

Thank you.

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A bit more background:

I'm deploying a Streamlit app on Google App Engine.
Streamlit web UI appear to be sending requests to the /healthz endpoint periodically, and when these requests fail, Streamlit app stops working and displays an error message as below.

Answer 1

Some URL paths ending in z, including /healthz, are reserved for use by App Engine and cannot be used.