If 'P' is the part name

The first form:

P.ReferencePoint(point=(0, 0, 0))

R= P.referencePoints[l]

P.DatumPointByOffset(point=R, vector=(10,0,0))

P.DatumPointByOffset(point=R, vector=(4,-4,0))

P.DatumPointByOffset(point=R, vector=(1,0,0))

K = P.datums.keys()

K.sort()

p1 = P.datums[K[2]]

p2 = P.datums[K[1]]

p3 = P.datums[K[0]]

P.DatumPlaneByThreePoints(point1=p1,point2=p2,point3=p3)

The second

P.ReferencePoint(point=(0, 0, 0))

R= P.referencePoints[l]

p3=P.DatumPointByOffset(point=R, vector=(10,0,0))

p2=P.DatumPointByOffset(point=R, vector=(4,-4,0))

p1=P.DatumPointByOffset(point=R, vector=(1,0,0))

P.DatumPlaneByThreePoints(point1=p1,point2=p2,point3=p3)

Thanks for reading.