python - Django: Rename file on upload to admin -

i have used function in django 1.6 rename files when uploaded through admin, not work in django 1.8. know if still possible in 1.8?

class entry(models.model):      def path_and_rename(path):         def wrapper(instance, filename):             ext = filename.split('.')[-1]             # filename             if instance.pk:                 filename = "%s-%s.%s" % (instance.pub_date.year,instance.issue, ext)             else:                 # set filename random strin                 filename = "%s.%s" % (uuid.uuid4(), ext)                 # return whole path file             return os.path.join(path, filename)         return wrapper       name = models.charfield(max_length=500)     pub_date = models.datetimefield()     issue = models.positiveintegerfield()        pdf = models.filefield(blank=true, upload_to=path_and_rename('uploads/pdf')) 

maybe need change way file uploaded using filefield. here link you.

when function upload_file gets called, can rename file in function.