code: def test_freq_view_safe(self):
      # Setting the freq for one DatetimeIndex shouldn't alter the freq
      #  for another that views the same data
  
      dti = date_range("2016-01-01", periods=5)
      dta = dti._data
  
      dti2 = DatetimeIndex(dta)._with_freq(None)
      assert dti2.freq is None
  
      # Original was not altered
      assert dti.freq == "D"
      assert dta.freq == "D"
  
imports: import pytest
  from pandas import DatetimeIndex, date_range
  from pandas.tseries.offsets import BDay, DateOffset, Day, Hour
label_desc: Use image node_id 3 for calling the TestFreq obj's underlying member method code with example usage: obj.test_freq_view_safe() without return types