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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 onCopySelection(self, event):
 """ Copies self.df_slice to the Clipboard if slice exists """

        if self.df_slice is not None:
            pd.DataFrame.to_clipboard(self.df_slice, header=False, index=False)
            self.grid.ClearSelection()
            self.df_slice = None
            print('-I- You have copied the selected cells.  You may paste them into a text document or spreadsheet using Command v.')
        else:
            print('-W- No cells were copied! You must highlight a selection cells before hitting the copy button.  You can do this by clicking and dragging, or by using the Shift key and click.')