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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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