title: Override KeyDown Event in wxPython
body: <p>I wrote wxTreeCtrl where I only want to handle keycodes between 65 and 90 (Ascii: A-Z).
  And I dont want to handle any other keycodes by myself. After I handled the keys between 65 and 90, how am I able to abort my event and use the standard "key down"-event for the wxTreeCtrl?</p>
  
  <p>Class definition:</p>
  
  <pre><code>class ConfigTreeCtrl(wx.TreeCtrl):
  </code></pre>
  
  <p>Method binding:</p>
  
  <pre><code>self.Bind(wx.EVT_KEY_DOWN, self.OnKeyDown, self)
  </code></pre>
  
  <p>Method definition:</p>
  
  <pre><code>def OnKeyDown(self, event):         
      now = time.time()  
      keyCode = event.GetKeyCode()
      if (keyCode &gt;= 65 and keyCode &lt;= 90) or ( keyCode &gt;= 48 and keyCode &lt;= 57):
          if self.searchString == "":
              self.searchString = chr(event.GetKeyCode())
          elif (now - self.lastKeyDown) &lt; 2:
              self.searchString += str(chr(event.GetKeyCode()))
          else:
              self.searchString = str(chr(event.GetKeyCode()))
      self.lastKeyDown = now
      self.GetItem(self.searchString, self.GetRootItem())
  </code></pre>
  
  <p>Thanks for your help and best regards</p>
  
  <p>Thomas</p>