Cannot Access Azure Key Vault from Python script via 'os.environ["VAULT_URL]" - Key Error: "VAULT_URL"

Question

I am having trouble accessing my Azure Key vault from my python script (debugging before deployment), the script cannot find the environment variable "VAULT_URL" even though I have set this in my environment variables on my Function App on Azure Portal.

All I need to do is retrieve secrets and use them later in the script, I am using this code as a direct copy/paste from this link to test Key vault connection and if it will work POST DEPLOYMENT https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-secrets/samples/hello_world.py#L37 :

app = func.FunctionApp()

the error it gives me is as follows

and here are my environment variables I want to access to be able to access my Key Vault both locally and after deployment

The error seems to surround the environment variable "VAULT_URL"

I have tried this code to retrieve secrets:

keyVaultName = "<keyVaultName>"
        KVUri = f"https://{keyVaultName}.vault.azure.net"

        credential = DefaultAzureCredential()
        client = SecretClient(vault_url=KVUri, credential=credential)

        #Salesforce Auth
        username = client.get_secret("username").value
        password = client.get_secret("password").value
        security_token = client.get_secret("security-token").value
        domain = client.get_secret("domain").value
        #SharePoint Auth
        sharepoint_username = client.get_secret("sharepoint-username").value
        sharepoint_password = client.get_secret("sharepoint-password").value
        sharepoint_clientID = client.get_secret("sharepoint-clientID").value
        sharepoint_clientSecret = client.get_secret("sharepoint-clientSecret").value
        sharepoint_tenantID = client.get_secret("sharepoint-tenantID").value
keyVaultName = 

Which worked locally, but when running remotely (after deployment), could not access the key vault, giving a 403 error, I have a managed instance which is assigned the role of Key Vault Administrator on my Key Vault but this did not work and so I decided it might have been something with my code that wasn't connecting to the key vault AFTER deployment