code: def test_background(self):
      x = np.array([[1, 0, 0], [1, 1, 5], [0, 0, 0]])
  
      assert_array_equal(label(x), [[1, 0, 0], [1, 1, 2], [0, 0, 0]])
  
      assert_array_equal(
          label(x, background=0), [[1, 0, 0], [1, 1, 2], [0, 0, 0]]
      )
  
imports: import numpy
  from skimage.measure import label
  import skimage.measure._ccomp
  from skimage._shared import testing
  from skimage._shared.testing import assert_array_equal
label_desc: Use image node_id 6 for calling the TestConnectedComponents obj's underlying member method code with example usage: obj.test_background() without return types