code: def test_single_value_numeric_no_pos_label(self):
      r0 = _get_labels_for_confusion_matrix([0], None)
      assert np.array_equal(r0, [0, 1])
      r1 = _get_labels_for_confusion_matrix([-1], None)
      assert np.array_equal(r1, [-1, 1])
      r2 = _get_labels_for_confusion_matrix([1], None)
      assert np.array_equal(r2, [np.iinfo(np.int64).min, 1])
  
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 4 for calling the TestGetLabelsForConfusionMatrix obj's underlying member method code with example usage: obj.test_single_value_numeric_no_pos_label() without return types