code: def test_forecast_multivariate(forecast, exp_index):
      assert forecast.prediction_length == len(exp_index)
      assert np.all(forecast.index == exp_index)
  
file_path: gluonts/test/torch/model/test_torch_forecast.py
imports: import numpy
  import pandas
  import pytest
  import torch
  from torch.distributions import Uniform
  from gluonts.torch.model.forecast import DistributionForecast
label_desc: Use image node_id 3 for calling a global function with example usage: test_forecast_multivariate(forecast, exp_index) without return types