Python for rhino 如何导出 rhino5

import rhinoscriptsyntax as rs
import time


def ExportIGESFile():
    filter="IGES files|.igs||"
    filter="Rhino 5 3D Models|.3dm||"
    filename=rs.SaveFileName("Rhino 5 3D Models export",filter)
    if not filename: return
    #make sure nothing is selected first
    rs.UnselectAllObjects()
    rs.SelectObjects(selection)
t = time.strftime('%Y%m%d_%H%M%S',time.localtime(time.time()))
PATH='C:\\test' + t

comm_opts='_Version=5 _SaveSmall=_No _GeometryOnly=_No _SaveTextures=_No _SavePlugInData=_No'

rs.Command("_-Export " +comm_opts + " "+ PATH + '.3dm' + " _Enter")