code: def test_seasonality_time_index(time_index):
      tt = Seasonality.from_index(time_index)
      assert tt.period == 5
  
      fcast = tt.out_of_sample(steps=12, index=time_index)
      new_idx = DeterministicTerm._extend_index(time_index, 12)
      pd.testing.assert_index_equal(fcast.index, new_idx)
  
imports: from statsmodels.compat.pandas import MONTH_END, PD_LT_1_0_0, QUARTER_END, YEAR_END, is_int_index
  from statsmodels.compat.pytest import pytest_warns
  from collections.abc import Hashable
  import numpy
  import pandas
  import pytest
  from statsmodels.tsa.deterministic import CalendarFourier, CalendarSeasonality, CalendarTimeTrend, DeterministicProcess, DeterministicTerm, Fourier, Seasonality, TimeTrend
label_desc: Use image node_id 19 for calling a global function with example usage: test_seasonality_time_index(time_index) without return types