 
   def as_json(result, json_opts \\ [])
 
+  def as_json({:ok, %Response{body: "", status_code: status}}, _json_opts) when (status >= 200) and (status < 300)  do
+    {:ok, nil}
+  end
   def as_json({:ok, %Response{body: body, status_code: status}}, json_opts) when (status >= 200) and (status < 300)  do
     Poison.decode(body, json_opts)
   end

        headers(op),
        http_options
      )

      case as_json(response) do
        {:error, _} -> response
        valid -> valid
      end
    end
  end


        headers(op),
        http_options
      )
      |> as_json
    end
  end
end
