code: def testPaddingFunctionReached(self):
      self.reached = False
  
      def padding_func(*unused_args):
          padding_func.called = True
          return [0, 0]
  
      conv1 = conv.ConvND(
          num_spatial_dims=2,
          output_channels=1,
          kernel_shape=3,
          stride=1,
          padding=padding_func,
          data_format="NHWC",
          **create_constant_initializers(1.0, 1.0, True),
      )
  
      conv1(tf.ones([1, 5, 5, 1], dtype=tf.float32))
  
      self.assertEqual(conv1.conv_padding, "VALID")
      self.assertEqual(conv1.padding_func, padding_func)
      self.assertTrue(getattr(padding_func, "called", False))
  
imports: from absl.testing import parameterized
  import numpy
  from sonnet.src import conv
  from sonnet.src import initializers
  from sonnet.src import test_utils
  import tensorflow
label_desc: Use image node_id 1 for calling the ConvTest obj's underlying member method code with example usage: obj.testPaddingFunctionReached() and returns: list