code: def _state_value(
      state: State, state_values: Mapping[State, float]
  ) -> float:
      return 0.0 if state not in state_values else state_values[state]
  
imports: import pickle
  from functools import reduce
  from typing import List, Mapping, Sequence
  import torch
  from reagent.ope.estimators.sequential_estimators import Model, RLPolicy, State, ValueFunction
  from reagent.ope.estimators.types import Action, ActionDistribution, ActionSpace
  from reagent.ope.test.envs import Environment, PolicyLogGenerator
  from reagent.ope.utils import RunningAverage
label_desc: Use image node_id 2 for calling the DPTrainer obj's underlying member method code with example usage: obj._state_value(state, state_values) and returns: unknown