Take a lists of strings or strings and flatten these into
    a list of strings.

    Arguments:
    - `*args`: "" or [""...]

    Return: [""...]
    Exceptions: None

def _stringlist(*args):
    """
    Take a lists of strings or strings and flatten these into
    a list of strings.

    Arguments:
    - `*args`: "" or [""...]

    Return: [""...]
    Exceptions: None
    """
    return list(itertools.chain.from_iterable(itertools.repeat(x,1) if stringy(x) else x for x in args if x))