code: def test_where_mismatched_nat(self, tz_aware_fixture):
      tz = tz_aware_fixture
      dti = date_range("2013-01-01", periods=3, tz=tz)
      cond = np.array([True, False, True])
  
      tdnat = np.timedelta64("NaT", "ns")
      expected = Index([dti[0], tdnat, dti[2]], dtype=object)
      assert expected[1] is tdnat
  
      result = dti.where(cond, tdnat)
      tm.assert_index_equal(result, expected)
  
imports: from datetime import date, datetime, time, timedelta
  import numpy
  import pytest
  from pandas._libs import index
  from pandas.compat.numpy import np_long
  import pandas
  from pandas import DatetimeIndex, Index, Timestamp, bdate_range, date_range, notna
  import pandas._testing
  from pandas.tseries.frequencies import to_offset
label_desc: Use image node_id 4 for calling the TestWhere obj's underlying member method code with example usage: obj.test_where_mismatched_nat(tz_aware_fixture) without return types