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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_all_values(self):
 """Returns a list of lists containing all cells' values as strings. .. note:: Empty trailing rows and columns will not be included. """


        data = self.spreadsheet.values_get(self.title)

        try:
            return fill_gaps(data['values'])
        except KeyError:
            return []