title: Drop down list dependent from another drop down tkinter
body: <p>I have one list with car brands in it and a second list with model names from these brands. I want to have two dropdown lists. First you select the brand and in the second dropdown you can select the model. But just models from the selected brand. I got the following code. </p>
  
  <pre><code>import tkinter as tk
  
  brands = ["Bugatti","VW","Opel","Porsche"]
  models = [["Veyron","Chiron"],
            ["Golf","Passat","Polo","Caddy"],
            ["Insignia","Corsa","Astra"],
            ["Taycan","Cayenne","911"]] 
  
  root = tk.Tk()
  canvas = tk.Canvas(root, height=500, width= 500, bg="white")
  canvas.pack()
  
  tkvar = tk.StringVar(root)
  tkvar.set('Choose')
  
  popupMenu1 = OptionMenu(canvas, tkvar, *brands)
  popupMenu1.pack()
  
  def change_dropdown(*args):
  
      print("Chosen brand " + tkvar.get())
  
      for i in range(len(brands)):
          if tkvar.get() == brands[i]:
              print(models[i])
  
  tkvar.trace('w', change_dropdown)
  root.mainloop()
  </code></pre>
  
  <p>How do i now create a second dropdown with the information from the list models. Thanks for your help.</p>