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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 onSelectAll(self, event):
 """ Selects full grid and copies it to the Clipboard """

        # do clean up here!!!
        if self.drop_down_menu:
            self.drop_down_menu.clean_up()
        # save all grid data
        self.grid_builder.save_grid_data()
        df = self.contribution.tables[self.grid_type].df
        # write df to clipboard for pasting
        # header arg determines whether columns are taken
        # index arg determines whether index is taken
        pd.DataFrame.to_clipboard(df, header=False, index=False)
        print('-I- You have copied all cells! You may paste them into a text document or spreadsheet using Command v.')