<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _split_list(cls, items, separator=",", last_separator=" and "):
 """ Splits a string listing elements into an actual list. Parameters items: :class:`str` A string listing elements. separator: :class:`str` The separator between each item. A comma by default. last_separator: :class:`str` The separator used for the last item. ' and ' by default. Returns ------- :class:`list` of :class:`str` A list containing each one of the items. """

        if items is None:
            return None
        items = items.split(separator)
        last_item = items[-1]
        last_split = last_item.split(last_separator)
        if len(last_split) > 1:
            items[-1] = last_split[0]
            items.append(last_split[1])
        return [e.strip() for e in items]