AttributeError：“ str”对象没有属性“ row”

Question

    import openpyxl as xl
    wb=xl.load_workbook("C:\\praveen\\python\\Excel\\Book1.xlsx")
    title_column_name="Name"
    ws=wb.active
    searchstring="joe"
    for row in list(ws.rows)[1:]:
        if row[1].value.find(searchstring)!= -1:
            print("found a matching row!slno={0}, name={1}, subject={2}, marks={3}".format(row[0].value, row[1].value, row[2].value. row[3].value))

错误输出： AttributeError：“ str”对象没有属性“ row”