code: def test_performance_warning():
      parameters = np.array([1, 0.1])
      nobs = 100
      resids = np.ones(nobs)
      sigma2 = resids.copy()
      p = 1
      backcast = 1.0
      var_bounds = np.empty((nobs, 2))
      var_bounds[:, 0] = 0.0
      var_bounds[:, 1] = 1.0e14
      with pytest.warns(PerformanceWarning):
          arch_recursion(
              parameters, resids, sigma2, p, nobs, backcast, var_bounds
          )
  
imports: from arch.compat.numba import PerformanceWarning
  import numpy
  import pytest
  from arch.univariate.recursions_python import arch_recursion
label_desc: Use image node_id 1 for calling a global function with example usage: test_performance_warning() without return types