code: def test_all_zeros(self):
      zeros = np.zeros(10)
  
      # Should behave as if pos_label=1
      assert metrics.true_positive_rate(zeros, zeros) == 0
      assert metrics.false_positive_rate(zeros, zeros) == 0
      assert metrics.true_negative_rate(zeros, zeros) == 1
      assert metrics.false_negative_rate(zeros, zeros) == 0
  
      assert metrics.true_positive_rate(zeros, zeros, pos_label=1) == 0
      assert metrics.false_positive_rate(zeros, zeros, pos_label=1) == 0
      assert metrics.true_negative_rate(zeros, zeros, pos_label=1) == 1
      assert metrics.false_negative_rate(zeros, zeros, pos_label=1) == 0
  
      assert metrics.true_positive_rate(zeros, zeros, pos_label=0) == 1
      assert metrics.false_positive_rate(zeros, zeros, pos_label=0) == 0
      assert metrics.true_negative_rate(zeros, zeros, pos_label=0) == 0
      assert metrics.false_negative_rate(zeros, zeros, pos_label=0) == 0
  
imports: import numpy
  import pytest
  import sklearn.metrics
  import fairlearn.metrics
  from fairlearn.metrics._base_metrics import _get_labels_for_confusion_matrix
label_desc: Use image node_id 1 for calling the TestSingleValueArrays obj's underlying member method code with example usage: obj.test_all_zeros() without return types