code: def test_infer_freq(self, freq_sample):
      # GH#11018
      idx = timedelta_range("1", freq=freq_sample, periods=10)
      result = TimedeltaIndex(idx.asi8, freq="infer")
      tm.assert_index_equal(idx, result)
      assert result.freq == freq_sample
  
label_desc: Use image node_id 1 for calling the TestTimedeltaIndexOps obj's underlying member method code with example usage: obj.test_infer_freq(freq_sample) without return types