public Task<GetVariantHeaderResponse> GetVariantHeaderAsync(GetVariantHeaderRequest request, IRequestOptions options = null)
 {
     return WebClient.SendAsync<GetVariantHeaderResponse>(HttpMethods.GET, request.BuildUrl(ClientSettings.Version), null, options);
 }
 public GetVariantHeaderResponse GetVariantHeader(GetVariantHeaderRequest request, IRequestOptions options = null)
 {
     return WebClient.Send(request, options);
 }