import re


def clean_skip_tags_option(tags_string):
    """
    Parse and clean skipped tags option

    * Separator can be "," or " " (or both)
    * Tags are de-duplicated
    * Tags are sorted alphabetically

    The output is separated by commas, without any space.
    """
    tags = re.split(r',| ', tags_string)
    tags = filter(bool, tags)
    tags = set(tags)
    tags = list(tags)
    tags = sorted(tags)
    return tags