[Python] GitHub Action - Deploy Python to Azure Function - import azure.identity not working

Problem I'm trying to deploy a Python Azure Function using GitHub Actions, but the deployment fails silently when my code includes azure-identity. The function works perfectly when deployed through VS Code, but not through GitHub Actions.

Environment Python 3.11 Azure Functions (Consumption Plan) GitHub Actions for deployment

Code: function_app.py:

import azure.functions as func
import logging
from azure.identity import DefaultAzureCredential
import json

app = func.FunctionApp(http_auth_level=func.AuthLevel.FUNCTION)

@app.route(route="fa_adtest_frontend_trigger")
def fa_adtest_frontend_trigger(req: func.HttpRequest) -> func.HttpResponse:
logging.info('Python HTTP trigger function processed a request.')
# When this import is removed, deployment works fine
credential = DefaultAzureCredential()
# Rest of the function code


Requirements.txt

azure-functions
azure-identity==1.15.0
requests
msal
azure-core
cryptography


Github Actions Workflow:

name: Deploy Python project to Azure Function App

env:
AZURE_FUNCTIONAPP_NAME: 'fa-apim-auth-frontend-001'
AZURE_FUNCTIONAPP_PACKAGE_PATH: 'src/function-apps/frontend'
PYTHON_VERSION: '3.11'

jobs:
deploy-function:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v4
- uses: actions/setup-python@v4
with:
python-version: ${{ env.PYTHON_VERSION }}

- name: 'Install Python Dependencies'
working-directory: ${{ env.AZURE_FUNCTIONAPP_PACKAGE_PATH }}
run: |
python -m pip install --upgrade pip wheel setuptools
mkdir -p .python_packages/lib/site-packages
pip install -r requirements.txt --target=".python_packages/lib/site-packages"

- name: 'Deploy Function'
uses: Azure/functions-action@v1
with:
app-name: ${{ env.AZURE_FUNCTIONAPP_NAME }}
package: ${{ env.AZURE_FUNCTIONAPP_PACKAGE_PATH }}
scm-do-build-during-deployment: true


Symptoms

• Function deploys and works when azure-identity import is removed
• When azure-identity is included, function doesn't appear in Azure portal after deployment
• No explicit errors in GitHub Actions logs
• Works fine when deployed through VS Code

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