auto save

diy-1.py

+new_data=''
+with open(r'C:\users\KK\desktop\test.txt','r',encoding='utf-8') as file:
+    for data in file:
+        if '小强:10本'in data:
+            data = data.replace('小强:10本','小强:11本')
+        if '小兰:12本'in data:
+            data = data.replace('小兰:12本','小兰:14本') 
+        new_data +=data
+
+with open(r'C:\users\KK\desktop\test.txt','w',encoding='utf-8') as file:
+    file.write(new_data)
+
+with open(r'C:\users\KK\desktop\test.txt','r',encoding='utf-8') as file:
+    a = file.read()
+    print(a)
\ No newline at end of file

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'
 # 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'
+file = open(r'c:\users\kk\desktop\test.txt','w',encoding = 'utf-8')
+file.write("小兰:12本\n")
+file.write("小强:10本\n")
+file.close()
\ No newline at end of file