How to manually release an additional slot from rate_limit

[gorootde]

I am doing API calls to a REST API that supports etag and conditional requests using If-None-Match. Here is some pseudo code:

rate_limit("api")
response=httpx.get(...)
if response.status_code == 304:
  # In this case my request was not counted against the rate limit by the API provider 
  return cached_response
else:
  return response

Since I need to use rate_limit before my API call, I already consumed one slot before I even know if I'd need to. So in case 304 is returned, I need to release the active slot I erroneously occupied.

Is there any API call to do so?