code: def test_submodules(self, num_layers, dropout_rate):
      mod = mlp.MLP([1] * num_layers, dropout_rate=dropout_rate)
      self.assertLen(mod.submodules, num_layers)
  
imports: import itertools
  from absl.testing import parameterized
  from sonnet.src import test_utils
  from sonnet.src.nets import mlp
  import tensorflow
label_desc: Use image node_id 2 for calling the MLPTest obj's underlying member method code with example usage: obj.test_submodules(num_layers, dropout_rate) without return types