create camera from viewport

createCam

import maya.cmds as mc

#find current cam
currentPan = None
currentPan = mc.getPanel(wf=True)

#check viewport is selected
exists = mc.modelPanel(currentPan, ex=True)
def createCam():
    if exists:
        #find current cam
        cam = mc.modelPanel(currentPan, q=True, camera=True)
    else:
        mc.confirmDialog(title='Warning', message='Please select viewport', button='ok') 
        return
    newCam = mc.duplicate(cam, name= 'cam0#')
    #show resolution gate
    mc.camera( newCam, e=True, dr=True )
    mc.setAttr(str(newCam[0])+'.visibility',1, e=True)
    
    #open in another window
    window = mc.window(widthHeight=(800, 800))
    mc.paneLayout()
    pan = mc.modelPanel()
    # display smooth shaded, no nurb curves
    mc.modelEditor(pan, e=True, da="smoothShaded", nc=False, gr=False)

    mc.lookThru(pan, newCam)
    mc.showWindow( window )
    
createCam()