title: python tkinter, how to get elements in root/notebook/Frame?
body: <p>I use tkinter to create gui</p>
  <pre><code>1、root = tk.Tk()
  
  2、tabControl = ttk.Notebook(root)
  //create one notebook
  
  3、tab1 = tk.Frame(tabControl, bg = 'blue', width = '400')
       tabControl.add(tab1, text = 'information')
  //create one Frame in notebook
  
  4、tree = ttk.Treeview(tab1,columns=ac)
  //create one tree view in Frame
  
  </code></pre>
  <p>such as:
  root
  --notebook
  ----Frame
  ------tree</p>
  <p>So, my question:</p>
  <p>If I get root, How can I get elements in root?</p>
  <p>For example, How can I get notebook/Frame/tree?</p>
  <p>Thanks very much for your help</p>