code: def test_timedelta_std(data, dtype, ddof):
      gsr = cudf.Series(data, dtype=dtype)
      psr = gsr.to_pandas()
  
      expected = psr.std(ddof=ddof)
      actual = gsr.std(ddof=ddof)
  
      if np.isnat(expected.to_numpy()) and np.isnat(actual.to_numpy()):
          assert True
      else:
          np.testing.assert_allclose(
              expected.to_numpy().astype("float64"),
              actual.to_numpy().astype("float64"),
              rtol=1e-5,
              atol=0,
          )
  
imports: import datetime
  import operator
  import cupy
  import numpy
  import pandas
  import pytest
  import cudf
  from cudf.testing import _utils
  from cudf.testing._utils import assert_eq, assert_exceptions_equal
label_desc: Use image node_id 29 for calling a global function with example usage: test_timedelta_std(data, dtype, ddof) without return types