docs: def tag_kind(tag, default=consts.TAG_KIND_UNKNOWN):
      """\
      Returns the TAG kind.
  
      `tag`
          A string.
      `default`
          A value to return if the TAG kind is unknown
          (set to ``constants.TAG_KIND_UNKNOWN`` by default)
      """
      if len(tag) == 2:
          return consts.TAG_KIND_GEO
      if u',' in tag:
          return consts.TAG_KIND_PERSON
      if tag[0] in u'Kk' and len(tag) == 4:
          return consts.TAG_KIND_PROGRAM
      t = tag.upper()
      if t in _TAGS_SUBJECT:
          return consts.TAG_KIND_SUBJECT
      if t in _TAGS_ORG:
          return consts.TAG_KIND_ORG
      return default