code: def stochastic_volatility_sp500():
      """Stochastic volatility model.
  
      This uses a dataset of 2517 daily returns of the S&P 500 index,
      representing the time period 6/25/2010-6/24/2020.
  
      Returns:
        target: StanModel.
      """
      dataset = data.sp500_returns()
      return stochastic_volatility.stochastic_volatility(**dataset)
  
imports: from inference_gym.internal import data
  from inference_gym.tools.stan import brownian_motion
  from inference_gym.tools.stan import eight_schools
  from inference_gym.tools.stan import item_response_theory
  from inference_gym.tools.stan import log_gaussian_cox_process
  from inference_gym.tools.stan import logistic_regression
  from inference_gym.tools.stan import lorenz_system
  from inference_gym.tools.stan import probit_regression
  from inference_gym.tools.stan import radon_contextual_effects
  from inference_gym.tools.stan import radon_contextual_effects_halfnormal
  from inference_gym.tools.stan import sparse_logistic_regression
  from inference_gym.tools.stan import stochastic_volatility
label_desc: Use image node_id 13 for calling a global function with example usage: stochastic_volatility_sp500() and returns: stochastic_volatility