Log Message:
py-jsonpickle: updated to 2.0.0

v2.0.0

Major release: the serialized JSON format now preserves dictionary identity, \ 
which is a subtle change in the serialized format.
Dictionary identity is now preserved. For example, if the same dictionary \ 
appears twice in a list, the reconstituted list will now contain two references \ 
to the same dictionary.

v1.5.2

Patch release to avoid the change in behavior from the preservation of dict \ 
identity. The next release will be v2.0.0.
This relese does not include the performance improvements from v1.5.1.
Pandas DataFrame objects with multilevel columns are now supported.
Numpy 1.20 is now officially supported.
Python 3.9 is now officially supported.
Achieved a small speedup for _get_flattener by merging type checks.

v1.5.1

The performance of the unpickler was drastically improved by avoiding tag checks \ 
for basic Python types.
decode() documentation improvements.
Serialization of Pandas DataFrame objects that contain timedelta64[ns] dtypes \ 
are now supported.
Dictionary identity is now preserved. For example, if the same dictionary \ 
appears twice in a list, the reconstituted list will now contain two references \ 
to the same dictionary.
Unit tests were added to ensure that sklearn.tree.DecisionTreeClassifier objects \ 
are properly serialized.
The is_reducible() utility function used by encode() is now 4x faster! Objects \ 
that provide __getstate__(), __setstate__(), and __slots__ benefit most from \ 
these improvements.
Improved pickler flatten()/encode() performance.

v1.5.0

Previous versions of jsonpickle with make_refs=False would emit null when \ 
encountering an object it had already seen when traversing objects. All \ 
instances of the object are now serialized. While this is arguably an \ 
improvement in the vast majority of scenarios, it is a change in behavior and is \ 
thus considered a minor-level change.
Multiple enums are now serialized correctly with make_refs=False.