code: def test_squezable_to_1d():
      data = co2.load().data
      data = data.resample(MONTH_END).mean().ffill()
      res = STL(data).fit()
      assert isinstance(res, DecomposeResult)
  
imports: from statsmodels.compat.pandas import MONTH_END
  import os
  import pickle
  import numpy
  from numpy.testing import assert_allclose
  import pandas
  import pytest
  from statsmodels.datasets import co2
  from statsmodels.tsa.seasonal import STL, DecomposeResult
label_desc: Use image node_id 23 for calling a global function with example usage: test_squezable_to_1d() without return types