code: def test_contains_nonunique(self, vals):
      # GH#9512
      idx = DatetimeIndex(vals)
      assert idx[0] in idx
  
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 2 for calling the TestContains obj's underlying member method code with example usage: obj.test_contains_nonunique(vals) without return types