- update to 0.27.0:
* Update uuidRepresentation warnings with "unspecified" as the
future default (instead of 'standard' previously advertised)
#2739
* Added `mongo_client_class` optional parameter to connect() to
allow to use an alternative mongo client than
pymongo.MongoClient.
* Fix DictField that always gets marked as changed #2606
* fix for Queryset.none() that has no effect on
update/aggregate / first #2669
* Changes in 0.26.0
* BREAKING CHANGE: Improved the performance of
:meth:`~mongoengine.Document.save()`
by removing the call to
:meth:`~mongoengine.Document.ensure_indexes` unless
``meta['auto_create_index_on_save']`` is set to True. With
the default settings, Document indexes will still be created
on the fly, during the first usage of the collection
(query, insert, etc), they will just not be re-created
whenever .save() is called.
* BREAKING CHANGE: remove deprecated method ``ensure_index``
(replaced by ``create_index`` long time ago).
* Addition of Decimal128Field:
:class:`~mongoengine.fields.Decimal128Field` for accurate
representation of Decimals (much better than the legacy field
DecimalField).
* BREAKING CHANGE: When using ListField(EnumField) or
DictField(EnumField), the values weren't always cast into the
Enum
* BREAKING CHANGE (bugfix) Querying ObjectIdField or