code: def oil():
      return [
          445.3641,
          453.1950,
          454.409,
          422.3789,
          456.0371,
          440.3866,
          425.1944,
          486.2052,
          500.4291,
          521.2759,
          508.9476,
          488.8889,
          509.8706,
          456.7229,
          473.8166,
          525.9509,
          549.8338,
          542.3405,
      ]
  
file_path: river/river/time_series/test_holt_winters.py
imports: from __future__ import annotations
  import io
  import pytest
  from river.time_series import HoltWinters
label_desc: Use image node_id 2 for calling a global function with example usage: oil() and returns: list