new_contents: import numpy as np
  from numpy.testing import assert_equal
  from gala import evaluate as ev
  
  def test_contingency_table():
      seg = np.array([0, 1, 1, 1, 2, 2, 2, 3])
      gt = np.array([1, 1, 1, 2, 2, 2, 2, 0])
      ct = ev.contingency_table(seg, gt, ignore_seg=[], ignore_gt=[])
      ct0 = ev.contingency_table(seg, gt, ignore_seg=[0], ignore_gt=[0])
      ctd = ct.todense()
      assert_equal(ctd, np.array([[0.   , 0.125, 0.   ],
                                  [0.   , 0.25 , 0.125],
                                  [0.   , 0.   , 0.375],
                                  [0.125, 0.   , 0.   ]]))
      assert ct.shape == ct0.shape
  
subject: Add test for contingency table fix