def get_indexes(seq, item):
    """Return all indexes of an item in a sequence.

    :param seq: sequence to check
    :param item: item to find indexes of
    :return: list of indexes
    """
    start_at = -1
    locs = []
    while True:
        try:
            loc = seq.index(item, start_at + 1)
        except ValueError:
            break
        else:
            locs.append(loc)
            start_at = loc
    return locs