code: func (bw *blobWriter) Cancel(ctx context.Context) error {
  	dcontext.GetLogger(ctx).Debug("(*blobWriter).Cancel")
  	if err := bw.fileWriter.Cancel(); err != nil {
  		return err
  	}
  
  	if err := bw.Close(); err != nil {
  		dcontext.GetLogger(ctx).Errorf("error closing blobwriter: %s", err)
  	}
  
  	return bw.removeResources(ctx)
  }
docs: // Cancel the blob upload process, releasing any resources associated with
  // the writer and canceling the operation.