public void FetchPicture()
 {
     if (_customer.Maybe(_ => _.PhotoURI) == null) return;
     var service = new CustomerService(new ApiConfiguration(), null, _keyService);
     service.GetPhotoAsync(_companyFile, _customer.UID, Credentials)
            .ContinueWith(t =>
                {
                    using (var stream = new MemoryStream(t.Result))
                    {
                        var bi = new BitmapImage();
                        bi.SetSource(stream);
                        Picture = bi;
                    }
                }, TaskScheduler.FromCurrentSynchronizationContext());
 }