code: def randn(self, shape, dtype):
      data = np.random.randn(*shape)
      if dtype == np.bool_:
          return data < 0  # Naive casting yields True with P(1)!
      else:
          return data.astype(dtype)
  
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 1 for calling the UnstackOpTest obj's underlying member method code with example usage: obj.randn(shape, dtype) and returns: unknown, data