title: How do I enable multiple selection of values from a combobox?
body: <p>Python 3.4.3, Windows 10, Tkinter</p>
  
  <p>I am attempting to create a combobox that allows for multiple selections from the dropdown. I have found similar work for listbox (<a href="https://stackoverflow.com/questions/14362116/python-tkinter-multiple-selection-listbox">Python Tkinter multiple selection Listbox</a>), but cannot get it work with the combobox. </p>
  
  <p>Is there a simple way to enable multiple selection from the dropdown of the combobox? </p>