A few internet references report that etags for the same underlying resource but with different representation (xml, json ...) should have different etags. That is currently not the case. Added code to allow incorporation of representation info into the etag. By default the representation is "json", but future patches can pass the representation down and modify flow to match requested representation.

try:
    # Python 3+
    from http import cookies as Cookie
    from http.cookies import CookieError, BaseCookie, SimpleCookie
    from http.cookies import _getdate as get_cookie_date
except:
    # Python 2.5-2.7
    from Cookie import CookieError, BaseCookie, SimpleCookie
    from Cookie import _getdate as get_cookie_date