code: def setUp(self):
      self.img = np.random.randint(0, 255, size=(3, 32, 48))
      self.mask = np.random.randint(
          0, 2, size=(self.n_bbox, 32, 48), dtype=bool
      )
      if self.label is not None:
          self.label = np.array(self.label, dtype=int)
      if self.score is not None:
          self.score = np.array(self.score)
  
file_path: chainercv/tests/visualizations_tests/test_vis_instance_segmentation.py
imports: import numpy
  import unittest
  from chainer import testing
  from chainercv.visualizations import vis_instance_segmentation
label_desc: Use image node_id 1 for calling the TestVisInstanceSegmentationInvalidInputs obj's underlying member method code with example usage: obj.setUp() without return types