code: def test_forward_no_cast_array(self):
      y = functions.cast(self.x, self.dtype)
      assert isinstance(y, chainer.Variable)
      assert y.data is self.x
  
imports: import unittest
  import numpy
  import chainer
  from chainer import functions
  from chainer import testing
  from chainer.testing import attr
  import chainerx
label_desc: Use image node_id 3 for calling the TestNoCast obj's underlying member method code with example usage: obj.test_forward_no_cast_array() without return types