[TheRealDanii]

Description

memorystore/redis/requirements.txt now needs Python 3.9 or newer (Flask 3.1.3, Werkzeug 3.1.9), but two of the deployment configs still target old runtimes:

• gke_deployment/Dockerfile builds on the deprecated gcr.io/google_appengine/python image and creates a python3.4 virtualenv, so Flask is never installed.
• gae_standard_deployment/app.yaml uses runtime: python37, which is deprecated on App Engine and can't install the pinned Flask.

Changes:

• The GKE Dockerfile now uses python:3.14-slim, the same base image as cloud_run_deployment/Dockerfile. It keeps the REDISHOST/REDISPORT defaults and the same gunicorn -b 0.0.0.0:8080 main:app command that visit-counter.yaml expects.
• app.yaml: python37 → python314, matching the python:3.14-slim image in the GKE Dockerfile.

How I tested (locally with podman, not on a live environment):

• podman build -f gke_deployment/Dockerfile . from memorystore/redis succeeds
• podman run --rm <img> python -c "import flask, redis, gunicorn, main" works
• With the default CMD, gunicorn boots and listens on 0.0.0.0:8080
• I did not deploy the App Engine change

Checklist

Testing

• I have tested this change on a live environment and verified it works as intended.

Compliance & Style

• I have followed the Sample Guidelines.
• The README is updated with all relevant information (if applicable). N/A: no README changes needed.
• If this PR adds a new sample directory: I updated the CODEOWNERS file. N/A: no new directory.

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Post-Approval Actions

• Please merge this PR for me once it is approved

[gemini-code-assist]

Code Review

This pull request updates the Python runtime environments for both the Google App Engine standard deployment and the GKE deployment. Specifically, it updates the App Engine runtime to Python 3.13 and modernizes the GKE Dockerfile to use a lightweight Python 3.14 image with optimized build steps. However, the App Engine standard environment does not currently support Python 3.13; it is recommended to downgrade this to Python 3.12 to prevent deployment failures.

[gemini-code-assist]

Google App Engine standard environment does not currently support the python313 runtime. The latest supported Python runtime is python312. Please use python312 to avoid deployment failures.

runtime: python312

[TheRealDanii]

python313 is GA on App Engine standard (supported until 2029-10-10, see https://cloud.google.com/appengine/docs/standard/lifecycle/support-schedule#python). Switched to python314 anyway to match the python:3.14-slim image used in the GKE Dockerfile.