Returns a list of all :class:`worksheets <gsperad.models.Worksheet>`
        in a spreadsheet.

def worksheets(self):
        """Returns a list of all :class:`worksheets <gsperad.models.Worksheet>`
        in a spreadsheet.

        """
        sheet_data = self.fetch_sheet_metadata()
        return [Worksheet(self, x['properties']) for x in sheet_data['sheets']]