title: Python/Tkinter - new window command
body: <p>I'm trying to open a window by clicking on a submenu button, but I can't, I saw some videos and posts, but I was unsuccessful in adding any of the commands. I'm using Python and Tkinter.</p>
  
  <p>Below is the source code:</p>
  
  <pre><code>from tkinter import *
  
  
  ftela = Tk()
  ftela.state("zoomed")
  ftela.title("OMNIA v0")
  menu = Menu(ftela)
  ftela.config(menu=menu)
  
  
  ##-----------------##
  ##     LABELS      ##
  ##-----------------##
  
  mylabel = LabelFrame(ftela, text="teste")
  mylabel.place(x=10, y=10, width=300, height=150)
  
  l_teste = Label(ftela, text="teste")
  l_teste.place(x=15, y=30)
  e_teste = Entry(ftela)
  e_teste.place(x=100, y=30)
  
  ##-----------------##
  ##     SUBMENU     ##
  ##-----------------##
  
  subMenu1=Menu(menu, tearoff=0)
  menu.add_cascade(label="Cadastro", menu=subMenu1)
  subMenu1.add_command(label="Empresas")
  subMenu1.add_command(label="Usuários")
  subMenu1.add_separator()
  subMenu1.add_command(label="Bancos/Caixas")
  subMenu1.add_command(label="Contas")
  
  
  ##-----------------##
  ##     MAINLOOP    ##
  ##-----------------##
  
  ftela.mainloop()
  
  </code></pre>