maya - Transfers ownership of elements in a set from one set to another

setAssignmentTransfer.py

import maya.cmds as mc
from pymel.core import *

def setAssignmentTransfer(shaderCurr, shaderNew, module='pymel'):
    '''
    transfer ownership of elements in a set from one set to another
    works on shaders and regular sets
    
    shaderCurr - <objectSet> the current set that holds the collection of objects to be transferred over
    shaderNew - <objectSet> the target set which to transfer the objects under
    module - <str> can be 'pymel' or 'cmds'
    '''
    def setAssignmentTransferCmds():
        sTime = mc.timerX()
        print 'shaderAssignmentTransfer start'
        sTimer = mc.timerX()
        # currObjsList = mc.ls(mc.sets(shaderCurr, q=True), flatten=False)
        # print currObjsList
        mc.sets(mc.sets(shaderCurr, q=True), e=True, forceElement=shaderNew)
        print 'time taken {}\n\n'.format(mc.timerX(startTime=sTimer))
    def setAssignmentTransferPymel():
        sTime = timerX()
        print 'shaderAssignmentTransfer start'
        sTimer = timerX()
        # currObjsList = ls(sets(shaderCurr, q=True), flatten=False)
        # print currObjsList
        sets(shaderNew, e=True, forceElement=sets(shaderCurr, q=True))
        print 'time taken {}\n\n'.format(timerX(startTime=sTimer))
        
    if not len(mc.ls([shaderCurr, shaderNew], type='objectSet'))==2:
        print 'Selection must be sets: Select current incoming set, then outgoing sets to transfer members to, then run the script again!'
        return
    if 'cmds' in module.lower():
        setAssignmentTransferCmds()
    else:
        setAssignmentTransferPymel()
    return
# run the script using pymel commands
# setAssignmentTransfer(mc.ls(sl=True)[0], mc.ls(sl=True)[1], module='pymel') # 0.55 seconds

# run the script using maya.cmds
setAssignmentTransfer(mc.ls(sl=True)[0], mc.ls(sl=True)[1], module='cmds') # 0.25 seconds

# cmds is almost twice as fast as pymel