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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_add(package, tag, pkghash):
 """ Add a new tag for a given package hash. Unlike versions, tags can have an arbitrary format, and can be modified and deleted. When a package is pushed, it gets the "latest" tag. """

    team, owner, pkg = parse_package(package)
    session = _get_session(team)

    session.put(
        "{url}/api/tag/{owner}/{pkg}/{tag}".format(
            url=get_registry_url(team),
            owner=owner,
            pkg=pkg,
            tag=tag
        ),
        data=json.dumps(dict(
            hash=_match_hash(package, pkghash)
        ))
    )