Pymongo / MongoDB: create index or ensure index?

Question

I don\'t understand the difference between create_index and ensure_index in pymongo. On the MongoDB indexes page, it says

yo

Answer 1

All indexes are permanent. ensure_index() is just a tiny wrapper around create_index().

""" The ensureIndex() function only creates the index if it does not exist. """

There is nothing like a transient index or a temporary index.