code: def test_l1_l2(self):
      value = np.random.random((4, 4))
      x = backend.Variable(value)
      y = regularizers.L1L2(l1=0.1, l2=0.2)(x)
      self.assertAllClose(
          y,
          0.1 * np.sum(np.abs(value)) + 0.2 * np.sum(np.square(value)),
      )
  
imports: import numpy
  from keras import backend
  from keras import regularizers
  from keras import testing
  from keras.regularizers.regularizers import validate_float_arg
label_desc: Use image node_id 4 for calling the RegularizersTest obj's underlying member method code with example usage: obj.test_l1_l2() without return types