docstr: Returns number of outputs that forward() call will return
  
  :return:
docstr_tok: ["Returns","number","of","outputs","that","forward","(",")","call","will","return",":","return",":"]
code: def num_outputs(self):
      """Returns number of outputs that forward() call will return
  
      :return:
      """
      assert (
          self._num_outputs is not None
      ), "must call forward() once to configure number of outputs"
      return self._num_outputs
  
imports: from typing import Dict, List, Union, Tuple
  import mxnet
  from mxnet.initializer import Initializer, register
  from mxnet.gluon import nn, loss
  from mxnet.ndarray import NDArray
  from mxnet.symbol import Symbol
  from rl_coach.base_parameters import AgentParameters
  from rl_coach.spaces import SpacesDefinition
label_desc: Use image node_id 3 for calling the Head obj's underlying member method code with example usage: obj.num_outputs() and returns: self