private async Task<RestResponse> InternalSendAsync(RestRequest request)
 {
     var result = await _restClient.SendAsync(request.Request);
     return new RestResponse(result);
 }
 public IAsyncOperation<RestResponse> SendAsync(RestRequest request)
 {
     Task<RestResponse> response = InternalSendAsync(request);
     return response.AsAsyncOperation<RestResponse>();
 }