from typing import Sequence


def flatten(nested: Sequence) -> list:
    """
    Return vectorized (1D) list from nested Sequence ``nested``.

    Args:
        nested: Sequence
           Iterable sequence containing multiple other nested sequences.

    Returns: list
        Vectorized (unidimensional) version of ``nested``.
    """

    return [lowest for sublist in nested for lowest
            in (flatten(sublist)
                if bool(isinstance(sublist, Sequence)
                        and not isinstance(sublist, str))
                else [sublist])]