code: def load_label(self, idx):
          
          label = Image.open('{}/SegmentationClass/{}.png'.format(self.dir, idx))
          label = np.array(label, dtype=np.uint8)
          label = label[np.newaxis, ...]
          return label
docs: Load label image as 1 x height x width integer array of label indices.
          The leading singleton dimension is required by the loss.