auto save

diy.py

-# 写入同学们的捐赠明细：'小兰：12本'、'小丽：11本'、'李文：9本'、'张伟：16本'
-file1= open(r'C:\Users\CM\Desktop\book.twt','w',encoding='utf-8')
-file1.write('小丽:11本\n')
-file1.write('李文:9本\n')
-file1.write('张伟:16本\n')
-file1.close()
-
-while open(r'C:\Users\CM\Desktop\book.txt','a',encoding='utf-8') as file:
-    file1.write('小强:10本\n')
-    file1.write('李明:15本\n')
-    file1.close()
 
 
+while open(r'C:\Users\CM\Desktop\book.txt','r',encoding='utf-8') as file1:\
+    for da in expression_list:
+        pass
\ No newline at end of file