ETag not available through SDK

[ibrechin]

I've been looking at using the REST API functionality to avoid update conflicts (https://www.twilio.com/docs/usage/mutation-and-conflict-resolution) but although the if_match param is supported by the python SDK, I can't see any way of accessing the ETag header from SDK objects, in the docs or the source code. Version.fetch only parses the response.text, as does Page.process_response.

Am I missing something or is this absent? If the latter, could some way of accessing the Etag be added?