save project

diy.py

+new_data=''
+with open(r'C:\Users\no3\Desktop\book.txt','r',encoding='utf-8') as file1:
+    for data in file1:
+        if '12345' in data:
+            data.replace('12345','12321')
+        new_data += data
+with open(r'C:\Users\no3\Desktop\book.txt','w',encoding='utf-8') as file1:
+    file1.write(new_data)
 
-with open(r'C:\Users\no3\Desktop\book.txt','w',encoding='utf-8') as file
-    for date in file:
-        if '123321' in date:
-            print("文件中有")
+with open(r'C:\Users\no3\Desktop\book.txt','r',encoding='utf-8') as file1:
+    a=file1.read()
+    print(a)
\ No newline at end of file