pub(super) fn step_2(
repr: &CompressedEdwardsY,
X: FieldElement51,
Y: FieldElement51,
Z: FieldElement51,
) -> EdwardsPointpub(super) fn step_2(
repr: &CompressedEdwardsY,
X: FieldElement51,
Y: FieldElement51,
Z: FieldElement51,
) -> EdwardsPoint