def uv60_to_uv76(u60, v60):     # CIE1960 to CIE1976
    """ convert CIE1960 uv to CIE1976 u"v" coordinates
    :param u60: u value (CIE1960)
    :param v60: v value (CIE1960)
    :return: CIE1976 u', v' """

    v76 = (3 * v60) / 2

    return u60, v76     # CIE1976 u', v'