openpyxl不能读取xls格式

python的openpyxl无法读取xls，后面下载了xlrd也无法读物xls格式。解决方法可以新建excel的xlsx格式的表。
打开格式可以read方式读取，运算速度也可以

如图，计算如下两列求和，举一反三

from openpyxl import load_workbook

def readxls(File):
    with open(File,'r') as f:
        data=f.read()
    return data


#求和
def countsum(wenjian):
    sum1 =0
    sum2 =0
    for i in wenjian.split('\n'):
        try:
            username=int(i.split('\t')[2])
            username1=int(i.split('\t')[4])
            sum1+=username
            sum2+=username1
        except:
            continue
    return sum1,sum2
    
#设备数剩余求和
def Summation():
    files="file.xls"  #这里修改下文件名
    wenjian = readxls(files)
    sumcount,sumcount1=countsum(wenjian)
    print("高仿版",sumcount)
    print("普通版",sumcount1)

if __name__ == "__main__":
    main1()