code: def testNpDoc(self):
      def np_fun(x):
          """np_fun docstring."""
          return
  
      @utils.np_doc(np_fun)
      def f():
          """f docstring."""
          return
  
      expected = """TensorFlow variant of `numpy.np_fun`.
  
  Unsupported arguments: `x`.
  
  f docstring.
  
  Documentation for `numpy.np_fun`:
  
  np_fun docstring."""
      self.assertEqual(f.__doc__, expected)
  
imports: import tensorflow.compat.v2
  from trax.tf_numpy.numpy_impl import utils
label_desc: Use image node_id 1 for calling the UtilsTest obj's underlying member method code with example usage: obj.testNpDoc() without return types