code: def test_std_execution(setup):
      raw1 = np.random.random((20, 25))
      raw2 = np.random.randint(10, size=(20, 25))
  
      arr1 = tensor(raw1, chunk_size=6)
  
      res1 = arr1.std().execute().fetch()
      expected1 = raw1.std()
      np.testing.assert_allclose(res1, expected1)
  
      res2 = arr1.std(axis=0).execute().fetch()
      expected2 = raw1.std(axis=0)
      np.testing.assert_allclose(res2, expected2)
  
      res3 = arr1.std(axis=1, keepdims=True).execute().fetch()
      expected3 = raw1.std(axis=1, keepdims=True)
      np.testing.assert_allclose(res3, expected3)
  
      arr2 = tensor(raw2, chunk_size=6)
  
      res1 = arr2.std().execute().fetch()
      expected1 = raw2.std()
      assert pytest.approx(res1) == expected1
  
      res2 = arr2.std(axis=0).execute().fetch()
      expected2 = raw2.std(axis=0)
      np.testing.assert_allclose(res2, expected2)
  
      res3 = arr2.std(axis=1, keepdims=True).execute().fetch()
      expected3 = raw2.std(axis=1, keepdims=True)
      np.testing.assert_allclose(res3, expected3)
  
      res4 = arr2.std(ddof=1).execute().fetch()
      expected4 = raw2.std(ddof=1)
      assert pytest.approx(res4) == expected4
  
      raw1 = sps.random(20, 25, density=0.1)
  
      arr1 = tensor(raw1, chunk_size=6)
  
      res1 = arr1.std().execute().fetch()
      expected1 = raw1.toarray().std()
      np.testing.assert_allclose(res1, expected1)
  
      arr2 = tensor(raw1, chunk_size=30)
  
      res1 = arr2.std().execute().fetch()
      expected1 = raw1.toarray().std()
      np.testing.assert_allclose(res1, expected1)
  
      arr = std(1)
      assert arr.execute().fetch() == 0
  
imports: import numpy
  import scipy.sparse
  import pytest
  from ....utils import ignore_warning
  from ...datasource import ones, tensor
  from ..None import mean, nansum, nanmax, nanmin, nanmean, nanprod, nanargmax, nanargmin, nanvar, nanstd, count_nonzero, allclose, array_equal, var, std, nancumsum, nancumprod
label_desc: Use image node_id 6 for calling a global function with example usage: test_std_execution(setup) without return types