# File lib/fog/identity/openstack/v3/models/tokens.rb, line 11
          def authenticate(auth)
            response = service.token_authenticate(auth)
            token_hash = response.body['token']
            Fog::Identity::OpenStack::V3::Token.new(
              token_hash.merge(:service => service, :value => response.headers['X-Subject-Token'])
            )
          end