def dedup_list(items):
    """ Performs a de-duplication routine on a list of strings.

    :param items: List of Strings
    :return: De-duplicated List of Strings
    """

    deduped = []
    pos = 0
    items.sort()
    for i in items:
        if i != items[pos - 1]:
            deduped.append(i)
        pos += 1
    del items
    return deduped