code: def test_autocorrelation_trivial():
      x = torch.zeros(10)
      actual = autocorrelation(x)
      assert_equal(actual, torch.ones(10), prec=0.01)
  
imports: import warnings
  import pytest
  import torch
  from pyro.ops.stats import _cummin, autocorrelation, autocovariance, crps_empirical, effective_sample_size, fit_generalized_pareto, gelman_rubin, hpdi, pi, quantile, resample, split_gelman_rubin, waic
  from tests.common import assert_close, assert_equal, xfail_if_not_implemented
label_desc: Use image node_id 10 for calling a global function with example usage: test_autocorrelation_trivial() without return types