I have a Python flask app that I want to deploy to an Azure Web App.

For some reason the venv that gets created during the build is not keeping the packages that get installed and I don’t understand why.
As an example, the requirements.txt has openai==1.12.0 in it.
The build job prints Successfully installed [...] openai-1.12.0 [...]. That sounds like it should be fine.

Then in the Azure shell of the web app after the deploy is successful I run pip list(with the antenv virtual enviroment active) to see what is installed and get a list with no openai. If I list the contents of the venv folder it contains all packages that I wanted installed…

This is the yaml for the build job:

          - script: |
              sudo apt-get install python3.11-dev portaudio19-dev
              ls
              python -m venv antenv
              source antenv/bin/activate
              python -m pip install --upgrade pip
              pip install -r ./requirements.txt
            workingDirectory: "$(projectRoot)"
            displayName: "Install requirements"

I also tried to change the pip install line to
pip install --target="./.python_packages/lib/site-packages" -r ./requirements.txt
with no luck, the packages are in that folder but not in use by the venv.
Am I doing anything obviously wrong? Any tips?