auto save

diy.py

 with open(r'c:\Users\chen\Documents\lesson13-1\sales_list.txt','r',encoding='utf-8') as file:
 with open(r'c:\Users\chen\Documents\lesson13-1\sales_list.txt','r',encoding='utf-8') as file:
-    a=file.read()
-    print(a)
+    a=file.readlines()
+    #print(a)
\ No newline at end of file
+list_sum=[]
+for i in a:
+    data=i.split()
+    sum=0
+    for sales in data[1:]:
+        sum=sum+int(sales)
+    r=data[0]+str(sum)+'\n'
+    list_sum.append(r)
+#写入文件
+with open(r'c:\Users\chen\Documents\lesson13-1\sales_list.txt','a',encoding='utf-8') as file:
+    file.writelines(list_sum)
\ No newline at end of file