code: def test_cummin_cummax(self, datetime_series, method):
      ufunc = methods[method]
  
      result = getattr(datetime_series, method)().values
      expected = ufunc(np.array(datetime_series))
  
      tm.assert_numpy_array_equal(result, expected)
      ts = datetime_series.copy()
      ts[::2] = np.nan
      result = getattr(ts, method)()[1::2]
      expected = ufunc(ts.dropna())
  
      result.index = result.index._with_freq(None)
      tm.assert_series_equal(result, expected)
  
file_path: pandas/pandas/tests/series/test_cumulative.py
imports: import numpy
  import pytest
  import pandas
  import pandas._testing
label_desc: Use image node_id 2 for calling the TestSeriesCumulativeOps obj's underlying member method code with example usage: obj.test_cummin_cummax(datetime_series, method) without return types