title: Sending a message to tkinter running GUI from an outside thread
body: <p>What is the best way to send a message to a tkinter frame from an outside thread without freezing the frame?</p>
  <p>I tried using bind and event_generate but the data field is missing in the event object (and not missing for the event_generate function):</p>
  <pre><code>class GUI(tk.Tk):
      ...
      def func(self, event)
          print(event.data) #AttributeError: 'Event' object has no attribute 'data'
  
      self.bind('&lt;&lt;test&gt;&gt;', func)
  
  class worker():
      ...
      self.event_generate('&lt;&lt;test&gt;&gt;', data = &quot;test_obj&quot;)
  </code></pre>
  <p>Thanks.</p>