def create_generator_of_subgroup(discriminant):
    """'Generator' as per Chia VDF competition.

    See: https://www.chia.net/2018/11/07/chia-vdf-competition-guide.en.html
    Note: This element generates a cyclic subgroup for given discriminant,
    not per se the entire group.
    """
    if (1 - discriminant) % 8 == 0:
        g = (2, 1, (1 - discriminant) // 8)
    else:
        g = None
    return g