code: def test_is_chained():
      arr = chainerx.array([1, 2], chainerx.float32)
      with pytest.raises(chainerx.ChainerxError):
          arr._is_chained()
  
      arr.require_grad()
      assert not arr._is_chained()
  
      arr2 = 2 * arr
      assert arr2._is_chained()
  
imports: import copy
  import math
  import pickle
  import numpy
  import pytest
  import chainerx
  import chainerx.testing
  from chainerx_tests import array_utils
label_desc: Use image node_id 35 for calling a global function with example usage: test_is_chained() without return types