code: def _assert_sequential_values(self, values, delta=1):
      unique_values = np.unique(values)
      paired_values = np.column_stack(
          (unique_values[:-1], unique_values[1:])
      )
      self.assertAllEqual(
          paired_values[:, 1] - paired_values[:, 0],
          np.ones((paired_values.shape[0],), np.int),
      )
  
file_path: luminoth/luminoth/models/fasterrcnn/fasterrcnn_test.py
imports: import numpy
  import tensorflow
  from easydict import EasyDict
  from luminoth.models.fasterrcnn import FasterRCNN
  from luminoth.utils.bbox_transform import clip_boxes
label_desc: Use image node_id 8 for calling the FasterRCNNNetworkTest obj's underlying member method code with example usage: obj._assert_sequential_values(values, delta) without return types