code: def test_square_as_first_layer(self):
      def z_func(x):
          return square(x)
  
      ll = Lambda(function=z_func, input_shape=[2, 3])
      seq = Sequential()
      seq.add(ll)
      result = seq.forward(np.ones([2, 3]))
      assert (result == np.ones([2, 3])).all()
  
imports: import keras.backend
  import keras.layers
  import numpy
  import pytest
  from test.zoo.pipeline.utils.test_utils import ZooTestCase
  from zoo.pipeline.api.autograd import *
  import zoo.pipeline.api.autograd
  from zoo.pipeline.api.keras.layers import *
  from zoo.pipeline.api.keras.models import Sequential, Model
  from zoo.pipeline.api.utils import remove_batch
label_desc: Use image node_id 19 for calling the TestOperator obj's underlying member method code with example usage: obj.test_square_as_first_layer() and returns: square