how to apply a time function in this script to add ob2 to the scene after ob1 without being together? import bge 
import bpy

scene = bge.logic.getCurrentScene()

ob = bge.logic.getCurrentController().owner

ob1 = scene.addObject("stone",ob)

ob2 = scene.addObject("twin",ob)
Its hard to tell if that's the optimal solution, but a "time function" in python can be summoned using the following commands:

import time
time.sleep(2)  # argument in seconds, int or float


The above function instructs the computer to wait idly for the determined amount of seconds.