[WxPython] TypeError: request for something already fulfilled?

[Yoriz]

This is not the same error, the error shows that your code has the following

hbox.Add(Eckpanel, 0, wx.EXPAND)

which is trying to add the class Eckpanel which should be an instance of Eckpanel.
you need to create the instance of Eckpanel passing it the parent and id arguments and add the result of that call to hbox's add method.