Maya Render frames for batch

renderFrames

import maya.cmds as mc
wName = "RenderFrames"

#Starting Class here
class renFrames(object):
    finLst = []
    cam = []
    finCam = ""
    def __init__(self):
        #print "testing"
        self.cam = mc.ls(cameras = True)
        self.finCam = self.defCam()
    
    def rngFrm(self,stFrm,enFrm):
        self.finLst = []
        if stFrm>enFrm:
            mc.confirmDialog(t="Invalid Range",m="Please enter the correct range (start frame must not be greater that end frame)", button="OK")
        else:
            for i in range(int(stFrm),int(enFrm)+1):
                self.finLst.append(i)
        #print self.finLst
    
    def changeView(self,item):
        if mc.optionMenu(opMenu,q=True,v=True) == "Render range of Frames":
            mc.formLayout(rrFrames,e=True,vis=True)
            mc.formLayout(rMFrames,e=True,vis=False)
            mc.text(rMlDesc,e=True,vis=False)
            mc.text(rML,e=True,vis=False)
            self.finLst = []
        else:
            mc.formLayout(rrFrames,e=True,vis=False)
            mc.formLayout(rMFrames,e=True,vis=True)
            mc.text(rMlDesc,e=True,vis=False)
            mc.text(rML,e=True,vis=False)
            self.finLst = []
        
    def defCam(self):
        for sCam in self.cam:
            if mc.getAttr(sCam+".renderable") == True:
                camDef = sCam
                #print sCam
        return camDef
        
    def chngRadio(self,cam):
        if mc.radioButtonGrp(selCam,q=True,sl=1) == 1:
            mc.optionMenu(lstCam,e=True,en=False)
            self.finCam = cam
        elif mc.radioButtonGrp(selCam,q=True,sl=2) == 2:
            mc.optionMenu(lstCam,e=True,en=True)
            self.finCam = mc.optionMenu(lstCam,q=True,v=True)
            
    def renScene(self):
        #print "Rendering Scene"
        if mc.optionMenu(opMenu,q=True,v=True) == "Render range of Frames":
            self.rngFrm(mc.intField(rStFr,q=True,v=True),mc.intField(rEnFr,q=True,v=True))
        
        if self.finCam == "Select Camera" or self.finCam =="":
            mc.confirmDialog(t="Select a Camera",m="Please select a camera before rendering the scene", button="OK")
        elif self.finLst == []:
            mc.confirmDialog(t="No Frames to Render",m="Please insert the frames before rendering the Scene", button="OK")
        else:
            print "Camera :",self.finCam
            print "Rendering Frames :",self.finLst
            mc.progressWindow(max=len(self.finLst),ii=True,st="",t="Render Frames")
            for i in range(0,len(self.finLst)):
                stat = "Rendering Frame ",str(i+1)," of ",str(len(self.finLst))
                #print stat
                if mc.progressWindow(q=True,ic=True) == True:
                    mc.progressWindow(e=True,ep=True)
                    break
                if mc.progressWindow(q=True,progress = True)>mc.playbackOptions(q=True,max=True):
                    mc.progressWindow(e=True,ep=True)
                    break
                mc.progressWindow(e=True,progress=i,st=stat)
                self.renderMe(self.finCam,self.finLst[i])
            mc.progressWindow(e=True,ep=True)
       
    def renderMe(self,cam,frame):
       print "Rendering frame ",frame," through ",cam
       mc.currentTime(frame)
       mc.render(cam)
    def genFrames(self,frame):
        self.finLst = []
        if frame == 0:
            mc.confirmDialog(t="Invalid Frames",m="Please enter Valid frames to insert the frames", button="OK")
        else:
            i=0
            while i<frame:
                res = mc.promptDialog(t="Insert Frame",m="Insert frame :"+str(i+1)+" of "+str(frame), button=["Insert","Cancel"], cb="Cancel",db="Insert",ds="Cancel")
                for j in range(0,len(self.finLst)):
                    if self.finLst[j] == int(mc.promptDialog(q=True,tx=True)):
                        i -=1
                        mc.confirmDialog(t="Frame exists",m="This frame already exist try another frame", button="OK")
                        self.finLst.remove(int(mc.promptDialog(q=True,tx=True)))
                        break
                if res != "Insert":
                    break
                else:
                    self.finLst.append(int(mc.promptDialog(q=True,tx=True)))
                    mc.text(rMlDesc,e=True,vis=True)
                    mc.text(rML,e=True,vis=True)
                i+=1
                mc.text(rML,e=True,l=str(self.finLst))
                
#Ending Calss Here
            
if mc.window('tester', exists=True):
    mc.deleteUI('tester')

ac = renFrames()
test = mc.window('tester',title=wName+"_v1.0", iconName=wName, widthHeight=(350,200), s=False)
#Main Context1
selForm = mc.formLayout()
selDesc = mc.text(l="Select what to do :", p=selForm)
opMenu = mc.optionMenu(changeCommand=ac.changeView)
mc.menuItem(label="Render range of Frames")
mc.menuItem(label="Render Missed Frames")
#Main Context1

#Main Context2
rrFrames = mc.formLayout(p=selForm)
rFDesc = mc.text(l="Enter Values for start and End frame range:", p=rrFrames)
rStFr = mc.intField(width=50,value=int(mc.getAttr("defaultRenderGlobals.startFrame")),cc = "ac.rngFrm(mc.intField(rStFr,q=True,v=True),mc.intField(rEnFr,q=True,v=True))", p=rrFrames)
rEnFr = mc.intField(width=50,value=int(mc.getAttr("defaultRenderGlobals.endFrame")),cc = "ac.rngFrm(mc.intField(rStFr,q=True,v=True),mc.intField(rEnFr,q=True,v=True))", p=rrFrames)
mc.formLayout(rrFrames, edit=True, vis=True,
    attachForm=[(rFDesc,'left',5),(rFDesc,'top',5),(rStFr,'left',5)],
    attachControl = [(rStFr,'top',5,rFDesc),(rEnFr,'left',3,rStFr),(rEnFr,'top',5,rFDesc)]
)
#ac.rngFrm(mc.textField(rStFr,q=True,tx=True),mc.textField(rEnFr,q=True,tx=True))
#Main Context2

#Main Context3
rMFrames = mc.formLayout(p=selForm)
rMDesc = mc.text(l="How many Frames to Render: ", p=rMFrames)
rMFr = mc.intField(width = 50, p=rMFrames)
rMBt = mc.button(l = "Enter Frames", p=rMFrames,c="ac.genFrames(mc.intField(rMFr,q=True,v=True))")
rMlDesc = mc.text(l="Frames Generated are:", p=rMFrames,vis=False)
rML = mc.text(l="",p=rMFrames,vis=False)
mc.formLayout(rMFrames, edit=True, vis=False,
    attachForm = [(rMDesc,'left',5),(rMDesc,'top',5),(rMFr,'top',3),(rMBt,'top',2),(rMlDesc,'left',5),(rML,'left',5)],
    attachControl = [(rMFr,'left',5,rMDesc),(rMBt,'left',5,rMFr),(rMlDesc,'top',10,rMDesc),(rML,'top',5,rMlDesc)]
)
#Main Context3

#Main Context1
frCamDesc = mc.text(l="Select Camera:", p = selForm)
selCam = mc.radioButtonGrp(p=selForm,numberOfRadioButtons = 2, label1 = ac.defCam(), label2="", select=1,cc = "ac.chngRadio(ac.defCam())")
lstCam = mc.optionMenu(p=selForm,en=False,cc=ac.chngRadio)
mc.menuItem(label="Select Camera")
mc.menuItem(label="")    
for selC in ac.cam:
    mc.menuItem(label=selC)
    
rend = mc.button(l="Render", p=selForm, width=100, command = "ac.renScene()")
clo = mc.button(l="Close", p=selForm, width=100, command = ('mc.toggleWindowVisibility(test )') )
#Main Context1

mc.formLayout(selForm, edit=True,
attachForm=[(selDesc,'left',10),(selDesc,'top',10),(opMenu,'top',7),(rend,'bottom',10),(clo,'bottom',10),(rrFrames,'left',10),(rMFrames,'left',10),(frCamDesc,'left',10)],
attachControl=[(opMenu,'left',5,selDesc),(clo,'left',2,rend),(rrFrames,'top',10,opMenu),(rMFrames,'top',10,opMenu),(frCamDesc,'bottom',15,rend),(selCam,'left',5,frCamDesc),(selCam,'bottom',11,rend),(lstCam,'left',0,selCam),(lstCam,'bottom',12,rend)],
attachPosition=[rend,'right',0,50])

mc.showWindow(test)