title: lambda to assign a value to global variable?
body: <p>I'm using tkinter and trying to assign a value to a global variable on a button press. Here is the code:</p>
  <pre><code>popup.add_command(label=&quot;Allow Moving Item&quot;, command=lambda: allowMoving=True)
  </code></pre>
  <p>I'm getting the invalid syntax. Can you tell me how to work this around?</p>