docs: 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