Show original filename and first 3 characters of hash in __str__ func

for datafile

portal/models.py

@@ -151,7 +151,7 @@ class DataFile(models.Model):
     objects = DataFileManager()
 
     def __str__(self):
-        return self.file.name
+        return "{} ({})".format(self.filename, self.file.name[:3])
 
     @property
     def filext(self):