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'
-j=open(r"C:\Users\EDZ\Documents\lesson12-2\ppp.txt","w",encoding="utf-8")
+j=open(r"C:\Users\EDZ\Documents\lesson12-4\ppp.txt","w",encoding="utf-8")
 j.write("小兰：12本\n")
 j.write("小丽：11本\n")
 j.write("李文：9本\n")
 j.write("张伟：16本\n")
 j.close()
 
-with open(r"C:\Users\EDZ\Documents\lesson12-2\ppp.txt","a",encoding="utf-8") as k:
+with open(r"C:\Users\EDZ\Documents\lesson12-4\ppp.txt","a",encoding="utf-8") as k:
     k.write("大兰：1000本\n")
-with open(r"C:\Users\EDZ\Documents\lesson12-2\ppp.txt","r",encoding="utf-8") as l:
+new=''
+with open(r"C:\Users\EDZ\Documents\lesson12-4\ppp.txt","r",encoding="utf-8") as l:
     for s in l:
         if "李文：9本\n" in s:
             print("ok")
+        new=s
+with open(r"C:\Users\EDZ\Documents\lesson12-4\ppp.txt","w",encoding="utf-8") as l:
\ No newline at end of file