code: def test_parametric_relu(self):
      layer = tl.ParametricRelu(a=0.25)
      x = np.array([-2.0, -1.0, 0.0, 2.0, 3.0, 5.0])
      y = layer(x)
      self.assertEqual(tl.to_list(y), [0.0, 0.0, 0.0, 0.5, 0.75, 1.25])
  
file_path: trax/trax/layers/activation_fns_test.py
imports: from absl.testing import absltest
  import numpy
  import trax.layers
label_desc: Use image node_id 2 for calling the ActivationFnsTest obj's underlying member method code with example usage: obj.test_parametric_relu() without return types