    # File lib/fog/openstack/requests/compute/list_usages.rb, line 6
            def list_usages(date_start = nil, date_end = nil, detailed=false)
              params = Hash.new
              params[:start] = date_start.iso8601.gsub(/\+.*/, '') if date_start
              params[:end]   = date_end.iso8601.gsub(/\+.*/, '')   if date_end
              params[:detailed] = (detailed ? '1' : '0')           if detailed

              request(
                :expects  => [200, 203],
                :method   => 'GET',
                :path     => 'os-simple-tenant-usage',
                :query    => params
              )
            end