def MovieMakerFileSelection(mm):
    assert isinstance(mm, poser.MovieMakerType)

    choices = mm.OutputFormats()
    with wx.SingleChoiceDialog(None,
                               caption="Moviemaker Filetypes",
                               message="Select one",
                               choices=choices,
                               style=wx.CHOICEDLG_STYLE
                               ) as dlg:
        if dlg.ShowModal() == wx.ID_OK:
            return dlg.GetSelection()
        else:
            return None


format = MovieMakerFileSelection(mm)
if format:
    mm.SetMovieFormat(format)

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