code: def test_dist(data, dist):
      df = 10 if dist == "t" else None
      pred = PredictionResults(data[0], data[1], dist=dist, df=df)
      basic = PredictionResults(data[0], data[1])
      ci = pred.conf_int()
      basic_ci = basic.conf_int()
      if dist == "t":
          assert np.all(np.asarray(ci != basic_ci))
      else:
          assert np.all(np.asarray(ci == basic_ci))
  
file_path: statsmodels/statsmodels/tsa/base/tests/test_prediction.py
imports: from statsmodels.compat.pandas import MONTH_END
  import numpy
  import pandas
  import pytest
  from scipy import stats
  from statsmodels.tsa.base.prediction import PredictionResults
label_desc: Use image node_id 3 for calling a global function with example usage: test_dist(data, dist) without return types