GetPointOnSurface don't exit

[xiix.xoox (Azure)]

I make script get location of surface but don’t exit. How can fix them?

import rhinoscriptsyntax as rs
import scriptcontext as sc
import Rhino

    class COT:
        def __init__(self,loca, txt):
            self.loca=loca
            self.txt=txt
        def getloca(self):
            return loca
        def gettxt(self):
            return txt
    LitextP=[]
    def Getlocatxt():
        while True:
            msg="Select suface:"
            srf_filter=Rhino.DocObjects.ObjectType.Surface 
            rc,objref=Rhino.Input.RhinoGet.GetOneObject(msg,False,srf_filter)
            if not objref:
                break
            #pt = rs.SurfaceAreaCentroid(objref)[0]
            pt=rs.GetPointOnSurface(objref)
            Loca = rs.coerce3dpoint(pt)
            text=str(round(Loca[2]))
            text=text.split('.')
            text=text[0]
            #Tao cot
            IT=COT(Loca,text)
            LitextP.append(IT)
            #rs.AddTextDot("C"+text,Loca)

    if __name__=="__main__":
        Getlocatxt()
        for tp in LitextP:
            print tp