code: def test_flatten_copied(self, xp):
      a = testing.shaped_arange((4,), xp)
      b = a.flatten()
      a[:] = 1
      return b
  
imports: import numpy
  import pytest
  import cupy
  from cupy import testing
  from cupy import _util
label_desc: Use image node_id 2 for calling the TestArrayFlatten obj's underlying member method code with example usage: obj.test_flatten_copied(xp) and returns: b