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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 add_worksheet(self, title, rows, cols):
 """Adds a new worksheet to a spreadsheet. :param title: A title of a new worksheet. :type title: str :param rows: Number of rows. :type rows: int :param cols: Number of columns. :type cols: int :returns: a newly created :class:`worksheets <gsperad.models.Worksheet>`. """

        body = {
            'requests': [{
                'addSheet': {
                    'properties': {
                        'title': title,
                        'sheetType': 'GRID',
                        'gridProperties': {
                            'rowCount': rows,
                            'columnCount': cols
                        }
                    }
                }
            }]
        }

        data = self.batch_update(body)

        properties = data['replies'][0]['addSheet']['properties']

        worksheet = Worksheet(self, properties)

        return worksheet