wxPython多个窗口的基本结构

如何在一个wxpython APP里面创建两个框架呢？

代码：

import ...import ...class MyFrame(wx.Frame):  def __init__(self):    wx.Frame.__init__(...class MyFrame2(wx.Frame):  def __init__(self):    wx.Frame.__init__(...class MyApp(wx.App):  def OnInit(self):    self.myframe = MyFrame()    self.myframe2 = MyFrame2()    self.SetTopWindow(self.myframe)    self.myframe.Show(True)    self.myframe2.Show(True)    return Trueif __name__=='__main__':  app = MyApp(0)  app.MainLoop()