Fibonacci spiral with respect to the Nautilus Shell

import rhinoscriptsyntax as rs

from math import *

import math as m

a = 1

b = 0.2

pts1 = []

pts2 = []

pts3 = []

for t in range(0, 30):

    x = a * m.exp(b*t) * m.cos(t)

    y = a * m.exp(b*t) * m.sin(t)

    pts1.append(rs.AddPoint(x/4,y/4,0))

    pts2.append(rs.AddPoint(x/1.3,y/1.3,15))

    pts3.append(rs.AddPoint(x,y,30))

curve1 = rs.AddInterpCurve(pts1)

curve2 = rs.AddInterpCurve(pts2)

curve3 = rs.AddInterpCurve(pts3)

# LOFTING SURFACE

strSurf = rs.AddLoftSrf([curve1, curve2, curve3])

listcurves = []

for i in range(0, 23):

    pointcoord1=rs.PointCoordinates(pts3[i])

    pointcoord1a=rs.PointCoordinates(pts3[i+1])

    

    pointcoord2=rs.PointCoordinates(pts3[i+6])

    pointcoord2a=rs.PointCoordinates(pts3[i+7])

    

    pointcoord3=rs.PointCoordinates(pts1[i])

    pointcoord3a=rs.PointCoordinates(pts1[i+1])

    

    pointcoord4=rs.PointCoordinates(pts1[i+6])

    pointcoord4a=rs.PointCoordinates(pts1[i+7])

    

    topcrv = rs.AddCurve([pointcoord2a, pointcoord2, pointcoord1, pointcoord1a])

    

    interpolcrv1 = rs.AddInterpCrvOnSrf(strSurf, [pointcoord1, pointcoord3])

    rs.ObjectColor(interpolcrv1,[255,0,0])

    interpolcrv2 = rs.AddInterpCrvOnSrf(strSurf, [pointcoord4, pointcoord3])

    rs.ObjectColor(interpolcrv2,[0,0,255])

   rs.AddLoftSrf([interpolcrv1, topcrv])