'Take an httplib2.Http instance (or equivalent) and authorizes it.
Authorizes it for the set of credentials, usually by replacing
http.request() with a method that adds in the appropriate headers and
then delegates to the original Http.request() method.
Args:
http: httplib2.Http, an http object to be used to make the refresh
request.'

def authorize(self, http):

    raise NotImplementedError
