code: def test_series(raw, series):
      result = series.rolling(50).apply(f, raw=raw)
      assert isinstance(result, Series)
      tm.assert_almost_equal(result.iloc[-1], np.mean(series[-50:]))
  
imports: import numpy
  import pytest
  from pandas import DataFrame, Index, MultiIndex, Series, Timestamp, concat, date_range, isna, notna
  import pandas._testing
  from pandas.tseries import offsets
label_desc: Use image node_id 14 for calling a global function with example usage: test_series(raw, series) without return types