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'
+
+with open(r'C:\Users\Administrator\Desktop\test.txt','r',encoding='utf-8') as file1:
+    data2 = ""
+    for data in file1:
+        if "小兰：12本" in data:
+            data = data.replace("小兰：12本","小兰：10本")
+        data2 = data2 + data
+    print(data2)
+
+with open(r'C:\Users\Administrator\Desktop\test.txt','w',encoding='utf-8') as file2:
+    file2.write(data2)
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