# History

Mar 27, 2023 V1.6.3
Apply to black code style. Migrate future to six


Oct 13, 2019 V1.5.6
Add ability to independently mutate multiple shallow copies of same initial tree.


Aug 10, 2017 V1.4.0
Abandon supporting Python 3.2 since v1.4.0.


Mar 27, 2014 V1.2.6
Node identifier supports multiple data types beyond int and str.
Finish depth() and leaves() routines.
Add siblings() routine.
Add unit test to the whole module.


Dec 21, 2013 V1.2.5
Add root() routine to Tree class.
Add all_nodes() routine to Tree class.


May 1, 2013
Pulish the module on PyPI with version 1.2 under GNU General Pulic License
version 3.  


Mar 21, 2013
Replace the list implementation with dict to improve performance to a
large extend. Thanks to @aronadaal


Dec 30, 2012
Make a pretty print routine to the tree and give some examples in README


Dec 19, 2012
Little modification and add get_node routine by @pgebhard.


Jul 13, 2012
Add rsearch routines to implement reversed searching from leaf to tree root.


Jul 07, 2012
Initiate the project on GitHub.
For my research paper, I need the python implementation of tree structure.
Based on the imcompleted code of Brett A. Kromkamp, I finished all methods
and added subtree and paste routines.
