auto save

diy.py

 file=open(r"C:\Users\Administrator\Desktop\12345.txt","w",encoding="utf-8")
 file=open(r"C:\Users\Administrator\Desktop\12345.txt","w",encoding="utf-8")
 file.write("小兰：12")
 file.write("小兰：12")
 file.close()
 file.close()
+with open(r'C:\Users\Administrator\Desktop\12345.txt',"a",encoding="utf-8")as file:
+   file.write("小明：10本")
\ No newline at end of file