send old backups to trash as well

aqt/main.py

@@ -2,9 +2,9 @@
 # -*- coding: utf-8 -*-
 # License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
-import os, sys, re, traceback, signal, send2trash
+import os, sys, re, traceback, signal
 import  zipfile
-
+from send2trash import send2trash
 from aqt.qt import *
 
 from anki import Collection
@@ -328,7 +328,7 @@ the manual for information on how to restore from an automatic backup."))
             delete = len(backups) + 1 - nbacks
             delete = backups[:delete]
             for file in delete:
-                os.unlink(os.path.join(dir, file[1]))
+                send2trash(os.path.join(dir, file[1]))
 
     def maybeOptimize(self):
         # have two weeks passed?
@@ -923,7 +923,7 @@ will be lost. Continue?"""))
         mdir = self.col.media.dir()
         for f in unused:
             path = os.path.join(mdir, f)
-            send2trash.send2trash(path)
+            send2trash(path)
         tooltip(_("Deleted."))
         diag.close()