diy.py

with open(r'c:\Users\joy\Documents\lesson13-1\sales_list.txt','r',encoding="utf-8")as file1:
     a=file1.readlines()
     #print(a)
fin_sun=[]
for i in a:
    num=i.split()
    #print(num[0])
    #print(num[1:])
    sun=0
    for seles in num[1:]:
        sun=sun+int(seles)
    res=num[0]+str(sun)+"\n"
    fin_sun.append(res)


with open(r'C:\Users\joy\Desktop\sales_list.txt','w',encoding="utf-8")as file1:
    file1.writelines(fin_sun)