code: def test_getitem(self, arr):
      dense = arr.to_dense()
      for i, value in enumerate(arr):
          tm.assert_almost_equal(value, dense[i])
          tm.assert_almost_equal(arr[-i], dense[-i])
  
imports: import numpy
  import pytest
  import pandas
  from pandas import SparseDtype
  import pandas._testing
  from pandas.core.arrays.sparse import SparseArray
label_desc: Use image node_id 1 for calling the TestGetitem obj's underlying member method code with example usage: obj.test_getitem(arr) without return types