code: def test_diff_execution(setup):
      data = np.array([1, 2, 4, 7, 0])
      x = tensor(data, chunk_size=2)
  
      t = diff(x)
  
      res = t.execute().fetch()
      expected = np.diff(data)
      np.testing.assert_equal(res, expected)
  
      t = diff(x, n=2)
  
      res = t.execute().fetch()
      expected = np.diff(data, n=2)
      np.testing.assert_equal(res, expected)
  
      data = np.array([[1, 3, 6, 10], [0, 5, 6, 8]])
      x = tensor(data, chunk_size=2)
  
      t = diff(x)
  
      res = t.execute().fetch()
      expected = np.diff(data)
      np.testing.assert_equal(res, expected)
  
      t = diff(x, axis=0)
  
      res = t.execute().fetch()
      expected = np.diff(data, axis=0)
      np.testing.assert_equal(res, expected)
  
      x = mt.arange("1066-10-13", "1066-10-16", dtype=mt.datetime64)
      t = diff(x)
  
      res = t.execute().fetch()
      expected = np.diff(
          np.arange("1066-10-13", "1066-10-16", dtype=np.datetime64)
      )
      np.testing.assert_equal(res, expected)
  
imports: import numpy
  import scipy.sparse
  import pandas
  import pytest
  from ....None import dataframe
  from ....None import tensor
  from ....None import execute, fetch
  from ....tests.core import require_cupy
  from ...datasource import tensor, ones, zeros, arange
  from ..None import copyto, transpose, moveaxis, broadcast_to, broadcast_arrays, where, expand_dims, rollaxis, atleast_1d, atleast_2d, atleast_3d, argwhere, array_split, split, hsplit, vsplit, dsplit, roll, squeeze, diff, ediff1d, flip, flipud, fliplr, repeat, tile, isin, searchsorted, unique, sort, argsort, partition, argpartition, topk, argtopk, trapz, shape, to_gpu, to_cpu, swapaxes
label_desc: Use image node_id 21 for calling a global function with example usage: test_diff_execution(setup) without return types