change keycode

I want to make a TextCtrl automatically convert inputted lowercases to
uppercases, so I use a EVT_CHAR:

class UpperCaseTextCtrl(wx.TextCtrl):
    def __init__(self, *a, **kw):
        ...
        wx.EVT_CHAR(self, self.on_char)

    def on_char(self, evt):
        keycode = evt.KeyCode()
        if chr(keycode) in string.lowercase:
            newkeycode = asc(chr(keycode).upper())
            WHAT_TO_DO_NOW() ???

How can I tell TextCtrl to use the newkeycode instead of keycode?
wx.KeyEvent seems has no SetKeyCode() alike method.

···

--
Qiangning Hong

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( "I'd love to go out with you, but I'm converting my )
( calendar watch from Julian to Gregorian." )
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