import openpyxl  ## initializing the xlsx xlsx = openpyxl.Workbook()  ## creating an active sheet to enter data sheet = xlsx.active  ## creating data to append data = [          [1, 2, 3],          [4, 5, 6],          [7, 8, 9],          [10, 11, 12]        ]  ## appending row by row to the sheet for row in data:     ## append method is used to append the data to a cell     sheet.append(row)  ## saving the xlsx file using 'save' method xlsx.save('appending.xlsx')

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