A newbie question about FileDialog in wxPython

[OhKyu Yoon]

Hi!
I am opening files using the wx.FileDialog in wxPython.
I want to modify the FileDialog such that some information about a 
highlighted file is displayed before I decide to open the file.
This is what I tried:

class ModifiedFileDialog(wx.FileDialog):
    def __init__(self,parent,message,wildcard,style):
        wx.FileDialog(self,parent,message,"","",wildcard,style)
        width,height = self.GetSizeTuple()
        self.SetSizeWH(width,height+100)
        # and so on...

I get an error when I try to change the size or make other changes.
Could someone tell me how to make this work or direct me to some reference?
Thank you.