python openpyxl修改excel

# -*- coding:utf8 -*-
from openpyxl import load_workbook


class KnowledgeComplete:

    def __init__(self, excel_name):

        self.excel_name = excel_name
        self.workbook = load_workbook(excel_name)
        self.worksheet = self.workbook['sheet1']

    def run(self):

        for row in range(2,self.worksheet.max_row):
            if (
                    not self.worksheet.cell(row=row, column=3).value
            ) and (
                    self.worksheet.cell(row=row, column=2).value
            ):
                self.worksheet.cell(row=row, column=3).value = "无"
                print(row)

        self.workbook.save(self.excel_name)


if __name__ == '__main__':
    k = KnowledgeComplete("pass.xlsx")
    k.run()