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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 username_to_uuid(username):
 """ Convert username to UUID. UUID('00fbac99-0bab-5e66-8e84-2e567ea4d1f6') """

    if not username.startswith('u-') or len(username) != 28:
        raise ValueError('Not an UUID based username: %r' % (username,))
    decoded = base64.b32decode(username[2:].upper() + '======')
    return UUID(bytes=decoded)