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\ColaMaster\Desktop\cola.txt","w",encoding="utf-8")
-file1.write("小兰：12本  ")
-file1.write("小丽：11本  ")
-file1.write("李文：9本  ")
-file1.write("张伟：16本  ")
+file1.write("小兰：12本\n")
+file1.write("小丽：11本\n")
+file1.write("李文：9本\n")
 file1.close()
 
 with open(r"C:\Users\ColaMaster\Desktop\cola.txt","a",encoding="utf-8") as file2:
-    file2.write("大白：100本")
+    file2.write("大白：100本\n")
     
+with open(r"C:\Users\ColaMaster\Desktop\cola.txt","r",encoding="utf-8") as file3:
+    a = file3.read()
+    if "小兰：12本" in a:
+        a = a.replace("小兰：12本","小兰：200本")
+
+with open(r"C:\Users\ColaMaster\Desktop\cola.txt","w",encoding="utf-8") as file4:
+    print(a)
+    file4.write(a)
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