code: def setUp(self):
      self.arr1 = np.array([[1, 2], [3, 4]])
      self.arr2 = np.array([[10, 2], [3, 4]])
      self.arr3 = np.array([[10, 2], [3, 40]])
      # Varying arrays, default bounds
      self.mat1 = Image(self.arr1, bounds=BoundingBox())
      self.mat2 = Image(self.arr2, bounds=BoundingBox())
      self.mat3 = Image(self.arr3, bounds=BoundingBox())
      # Varying arrays, different bounds
      self.mat4 = Image(self.arr1, bounds=BoundingBox(radius=0.3))
      self.mat5 = Image(self.arr2, bounds=BoundingBox(radius=0.3))
  
imports: import numpy
  from holoviews import Image
  from holoviews.core import BoundingBox, Dimension
  from holoviews.core.element import HoloMap
  from holoviews.element.comparison import ComparisonTestCase
label_desc: Use image node_id 1 for calling the RasterTestCase obj's underlying member method code with example usage: obj.setUp() without return types