Wxtimer...I need to close a dialog after a particular time...

Hello all,
Actually i need to close a dialog automatically after 5-6 seconds.
For it what should i do,please help me.I am using wxTimer
[code]self.MB =wx.Dialog(self,-1,"hello",pos=(-1,-1),size=(200,100),style=wx.NO_3D)
self.MB.Show(True)
self.timer = wx.Timer(5,self.Step(self))
self.timer.Start()


def Step:if self.timer.IsRunning():
print ""
else:self.MB.Close(True)
[code]
Is this code is not correct or what?
Please help me.