code: def setUp(self):
      if self.no_img:
          self.img = None
      else:
          self.img = np.random.randint(0, 255, size=(3, 32, 48))
      self.label = np.random.randint(-1, 3, size=(48, 64)).astype(
          np.int32
      )
  
file_path: chainercv/tests/visualizations_tests/test_vis_semantic_segmentation.py
imports: import numpy
  import unittest
  from chainer import testing
  from chainercv.visualizations import vis_semantic_segmentation
label_desc: Use image node_id 1 for calling the TestVisSemanticSegmentation obj's underlying member method code with example usage: obj.setUp() without return types