auto save

66.py

 # file1=open(r"C:\Users\Administrator\Desktop\test.txt","w",encoding='utf-8')
 # file1.write('小兰:12本')
 # file1.close()
-# file1=open(r"C:\Users\Administrator\Desktop\test.txt","w",encoding='utf-8')
-# file1.write('老马:12本\n')
-# file1.write('小强:10本\n')
-# file1.close()
+file1=open(r"C:\Users\Administrator\Desktop\test.txt","w",encoding='utf-8')
+file1.write('老马:12本\n')
+file1.write('小强:10本\n')
+file1.close()
 # file1=open(r"C:\Users\Administrator\Desktop\test.txt","a",encoding='utf-8')
 # file1.write('小兰:12本')
 # file1.close()
-with open(r"C:\Users\Administrator\Desktop\test.txt","a",encoding='utf-8') as
-file:
-    file.write('小兰:12本')
\ No newline at end of file
+with open(r"C:\Users\Administrator\Desktop\test.txt","a",encoding='utf-8')as file:
+    file.write('小兰:12本')
+new_data=''
+with open(r"C:\Users\Administrator\Desktop\test.txt","r",encoding='utf-8')as file1:
+    for data in file1:
+        if'小强:10本' in data:
+            data=data.replace('小强:10本','小强:11本')
+        new_data+=data
+with open(r"C:\Users\Administrator\Desktop\test.txt","w",encoding='utf-8')as file1:
+    file1.write(new_data)
\ No newline at end of file