code: def _define_program(self):
      self.ensemble_predict_program = fluid.Program()
      self.startup_program = fluid.Program()
      with fluid.program_guard(
          self.ensemble_predict_program, self.startup_program
      ):
          obs = layers.data(
              name="obs", shape=[OBS_DIM], dtype="float32"
          )
          action = self._ensemble_predict(obs)
          self.ensemble_predict_output = [action]
  
imports: import numpy
  import parl.layers
  from mlp_model import ActorModel, CriticModel
  from paddle import fluid
  from parl.utils import logger
label_desc: Use image node_id 3 for calling the EnsembleBaseModel obj's underlying member method code with example usage: obj._define_program() without return types