from tkinter import *
import tkinter.ttk as ttk

def derp1(typeof,obj):
    obj.append(typeof)

def mainfunc():
    root=Tk()
    test = list()
    button=Button(root,text="label",command=lambda: derp1(Label,test))
    button2=Button(root,text="button",command=lambda: derp1(Button,test))
    button3=Button(root,text="entry",command=lambda: derp1(Entry,test))
    button4=Button(root,text="save",command=lambda: root.quit())
    button.grid()
    button2.grid()
    button3.grid()
    button4.grid()
    root.mainloop()
    root.destroy()
    return test[0]

def getobj(root,obj):
    obj = mainfunc()(root)
    obj.grid()

diffroot = Tk()
obj = object()
button=Button(diffroot,text="add",command=lambda: getobj(diffroot,obj))
button.grid()
diffroot.mainloop()