code: def test_contains_with_missing_value(self):
      # GH#19132
      idx = MultiIndex.from_arrays([[1, np.nan, 2]])
      assert np.nan in idx
  
      idx = MultiIndex.from_arrays([[1, 2], [np.nan, 3]])
      assert np.nan not in idx
      assert (1, np.nan) in idx
  
imports: from datetime import timedelta
  import re
  import numpy
  import pytest
  from pandas._libs import index
  from pandas.errors import InvalidIndexError, PerformanceWarning
  import pandas
  from pandas import Categorical, DataFrame, Index, MultiIndex, date_range
  import pandas._testing
label_desc: Use image node_id 4 for calling the TestContains obj's underlying member method code with example usage: obj.test_contains_with_missing_value() without return types