Series создан как:import pandas as pds = pd.Series(pd.array([None, 10, None, 30, None], dtype='Int64'))Что вернёт s.ffill().tolist()?
[<NA>, 10, 10, 30, 30]
[10, 10, 10, 30, 30]
[<NA>, 10, 30, 30, <NA>]
[10, 10, 30, 30, 30]
[<NA>, 10, <NA>, 30, <NA>]
