ModuleNotFoundError: No module named 'azure.identity'

I am making a foray into writing a webhook listener in Visual Studio Code using Python. I will admit I am a tyro, so do bear with me. The initial example in VSC for a webhook listener is straightforward. I run it locally in my terminal window using func host start, I then test it using Postman in VSC and get the expected response and a 200 status.

But I want to do more than simply give a response/200, I want to grab the incoming JSON data, store it in Azure Data Lake, and then give a response. To do this, I have to add some libraries. The imports in my function_app.py file have gone from

import loggingimport azure.functions as func

to this

import loggingimport datetimeimport osimport jsonimport azure.functions as funcfrom azure.identity import DefaultAzureCredentialfrom azure.keyvault.secrets import SecretClientfrom azure.storage.filedatalake import DataLakeServiceClient

I updated my requirements.txt file so that it went from

# DO NOT include azure-functions-worker in this file# The Python Worker is managed by Azure Functions platform# Manually managing azure-functions-worker may cause unexpected issuesazure-functions

to this

# DO NOT include azure-functions-worker in this file# The Python Worker is managed by Azure Functions platform# Manually managing azure-functions-worker may cause unexpected issuesazure-functionsazure-storage-file-datalakeazure-identityazure-keyvaultrequests

My local.settings.json now includes entries for KEY_VAULT_URL, STORAGE_ACCOUNT_NAME, etc.

Thinking all is set, I kick off the code in the terminal window using func host start and now get an error that boils down to ModuleNotFoundError: No module named 'azure.identity'.

Somewhere it seems I've not told VSC where azure.identity exists. It is in .venv\Lib\site-packages\azure_identity-1.16.0.dist-info.

I know I'm probably missing something very obvious to others, but I would be grateful for any suggestions.

I have tried researching, using ChatGPT, GitHub Copilot, etc. but nothing seems to make a difference.

I have performed pip installs of individual packages, I've done a pip install -r requirements.txt to ensure everything was available. I'm honestly at a loss.