code: def input_prototype(self):
      return self.q_network.input_prototype()
  
file_path: ReAgent/reagent/models/bcq.py
imports: import torch
  from reagent.core import types
  from reagent.models.base import ModelBase
label_desc: Use image node_id 2 for calling the BatchConstrainedDQN obj's underlying member method code with example usage: obj.input_prototype() and returns: self