Question: OAuth2 access token from AAD and forward it to the backend

I've been looking at
https://github.com/Azure/api-management-policy-snippets/blob/47a03189f4fd75563ae2c234a13510dd6e23e6db/examples/Get%20OAuth2%20access%20token%20from%20AAD%20and%20forward%20it%20to%20the%20backend.policy.xml#L23

and had a question to @mike-urnun-msft about caching and checking token expiration time.

Shouldn't OAUTH policy include those to avoid calls to AAD when still valid token could be cached?

Read examples/Get OAuth2 access token from AAD and forward it to the backend.policy.xml at line 23. Investigate whether the policy should cache tokens and check expiration before calling AAD. The issue does not specify tests or acceptance criteria, so completion would need maintainer agreement on the expected behavior.

Written by the indexing model from the issue text.