docs: def split(series):
      '''
      Split values.
  
      The index is dropped, but this may change in the future.
  
      Parameters
      ----------
      series : ~pandas.Series[~pytil.numpy.ArrayLike]
          Series with array-like values.
  
      Returns
      -------
      ~pandas.Series
          Series with values split across rows.
  
      Examples
      --------
      >>> series = pd.Series([[1,2],[1,2],[3,4,5]])
      >>> series
      0       [1, 2]
      1       [1, 2]
      2    [3, 4, 5]
      dtype: object
      >>> split(series)
      0    1
      1    2
      2    1
      3    2
      4    3
      5    4
      6    5
      dtype: object
      '''
      s = df_.split_array_like(series.apply(list).to_frame('column'), 'column')['column']
      s.name = series.name
      return s