Delete duplicates from GoogleAppEngine Model?
Quick? Probably not.
If you did want to delete dupes, my approach would be to write a remote_api script. Query the model for all entities, sort by title, and fetch batches of 100. Keep a local Python dictionary of titles. If you encounter a new title, add it to the dictionary. If you encounter a known title, add the entity to a delete batch, and flush the deletes before moving on to the next query batch.
Probably an excessive amount of work when you can just wipe out your datastore and re-import instead.
I have two Google App Engine Models.  I ran my cron's a few times and now there are duplicate entries in my datastore.  If it was easy to just delete my entire datastore and upload my data again I would.  BUT it took 4 hours to upload last time so I am wondering is there a quick way of deleting entries with duplicate names in the "title" field within the model?