code: def test_sparse_ff_kernel_scaling(self):
      d_model = 8
      n_elements_in_block = 2
      d_ff = 16
      x_shape = (2, 8, d_model)
      temperature = 0.7
      with fastmath.use_backend(fastmath.Backend.JAX):
          x = np.ones(x_shape).astype(np.float32)
          input_signature = shapes.signature(x)
          model = sparsity.SparseFF(
              d_ff=d_ff,
              n_elements_in_block=n_elements_in_block,
              temperature=temperature,
              ff_chunk_size=4,
              mode="train",
              kernel_scaling=True,
          )
          weights, state = model.init(input_signature)
          out, _ = model.pure_fn(
              x, weights, state, rng=jax.random.PRNGKey(0)
          )
          self.assertEqual(out.shape, x.shape)
  
imports: import functools
  from absl.testing import parameterized
  import jax
  import numpy
  from tensorflow import test
  from trax import fastmath
  from trax import shapes
  import trax.layers
  from trax.layers import test_utils
  from trax.layers.research import sparsity
label_desc: Use image node_id 6 for calling the EfficientFeedForwardTest obj's underlying member method code with example usage: obj.test_sparse_ff_kernel_scaling() without return types