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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_csv_export_info(self, preview_data):
 """Shows csv export preview dialog and returns csv_info csv_info is a tuple of dialect, has_header, digest_types Parameters preview_data: Iterable of iterables \tContains csv export data row-wise """


        preview_rows = 100
        preview_cols = 100

        export_preview = list(list(islice(col, None, preview_cols))
                              for col in islice(preview_data, None,
                                                preview_rows))

        filterdlg = CsvExportDialog(self.main_window, data=export_preview)

        if filterdlg.ShowModal() == wx.ID_OK:
            dialect, has_header = filterdlg.csvwidgets.get_dialect()
            digest_types = [types.StringType]
        else:
            filterdlg.Destroy()
            return

        filterdlg.Destroy()

        return dialect, has_header, digest_types