import re


def split_string(instr, item, split):
    """
    Split instr as a list of items separated by splits.

    @param instr: string to be split
    @param item: regex for item to be split out
    @param split: regex for splitter
    @return: list of strings
    """
    if not instr:
        return []
    return [h.strip() for h in re.findall(
        r'%s(?=%s|\s*$)' % (item, split), instr
    )]