code: def testAxis0Default(self):
      a = constant_op.constant([[1, 2, 3], [4, 5, 6]], name="a")
      unstacked = self.evaluate(array_ops_stack.unstack(a))
  
      self.assertEqual(len(unstacked), 2)
      self.assertAllEqual(unstacked[0], [1, 2, 3])
      self.assertAllEqual(unstacked[1], [4, 5, 6])
  
imports: import numpy
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import array_ops_stack
  from tensorflow.python.ops import gradient_checker_v2
  from tensorflow.python.platform import test
label_desc: Use image node_id 12 for calling the UnstackOpTest obj's underlying member method code with example usage: obj.testAxis0Default() without return types