Access headers to get 'X-DayLimit-Remaining'

[Zylatis]

According to the Xero docs the remaining API call limit is returned in this header, is there a way to get this for each set of requests the module is using? For example i am currently using contact.get()

Also a related question which I can't seem to answer myself by just looking at the code: if i do something like contacts.all() is that a single request or is that going to first do a lookup of all the contact ids and then do individual requests?

Basically what I'm after is a batch of data which is the outstanding balance for each contact.

[Zylatis]

Ah I see actually the 'since' does what I want for the most part for the 2nd query, however I'd still like to understand if single queries are being made and how to obtain the headers after a response is received.