code: def test_pi():
      x = torch.randn(1000).exp()
      assert_equal(pi(x, prob=0.8), quantile(x, probs=[0.1, 0.9]))
  
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 3 for calling a global function with example usage: test_pi() without return types