code: def test_conv_constraints(self):
      layer = layers.Conv2D(
          filters=4,
          kernel_size=3,
          kernel_constraint="non_neg",
      )
      layer.build((None, 5, 5, 3))
      self.assertIsInstance(layer.kernel.constraint, constraints.NonNeg)
      layer = layers.Conv2D(
          filters=4,
          kernel_size=3,
          bias_constraint="non_neg",
      )
      layer.build((None, 5, 5, 3))
      self.assertIsInstance(layer.bias.constraint, constraints.NonNeg)
  
imports: import numpy
  import pytest
  from absl.testing import parameterized
  from numpy.lib.stride_tricks import as_strided
  from keras import constraints
  from keras import layers
  from keras import testing
label_desc: Use image node_id 4 for calling the ConvCorrectnessTest obj's underlying member method code with example usage: obj.test_conv_constraints() without return types