MAINT set version to 1.6.dev0 and add 1.6 changelog (#28962)

doc/whats_new.rst

@@ -15,6 +15,7 @@ Changelogs and release notes for all scikit-learn releases are linked in this pa
 .. toctree::
    :maxdepth: 2
 
+   whats_new/v1.6.rst
    whats_new/v1.5.rst
    whats_new/v1.4.rst
    whats_new/v1.3.rst

doc/whats_new/v1.6.rst

@@ -0,0 +1,42 @@
+.. include:: _contributors.rst
+
+.. currentmodule:: sklearn
+
+.. _release_notes_1_6:
+
+===========
+Version 1.6
+===========
+
+..
+  -- UNCOMMENT WHEN 1.6.0 IS RELEASED --
+  For a short description of the main highlights of the release, please refer to
+  :ref:`sphx_glr_auto_examples_release_highlights_plot_release_highlights_1_6_0.py`.
+
+.. include:: changelog_legend.inc
+
+.. _changes_1_6:
+
+Version 1.6.0
+=============
+
+**In Development**
+
+Changelog
+---------
+
+..
+    Entries should be grouped by module (in alphabetic order) and prefixed with
+    one of the labels: |MajorFeature|, |Feature|, |Efficiency|, |Enhancement|,
+    |Fix| or |API| (see whats_new.rst for descriptions).
+    Entries should be ordered by those labels (e.g. |Fix| after |Efficiency|).
+    Changes not specific to a module should be listed under *Multiple Modules*
+    or *Miscellaneous*.
+    Entries should end with:
+    :pr:`123456` by :user:`Joe Bloggs <joeongithub>`.
+    where 123455 is the *pull request* number, not the issue number.
+
+Thanks to everyone who has contributed to the maintenance and improvement of
+the project since version 1.5, including:
+
+TODO: update at the time of the release.

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "scikit-learn"
-version = "1.5.dev0"
+version = "1.6.dev0"
 description = "A set of python modules for machine learning and data mining"
 readme = "README.rst"
 maintainers = [

sklearn/__init__.py

@@ -42,7 +42,7 @@ logger = logging.getLogger(__name__)
 # Dev branch marker is: 'X.Y.dev' or 'X.Y.devN' where N is an integer.
 # 'X.Y.dev0' is the canonical version of 'X.Y.dev'
 #
-__version__ = "1.5.dev0"
+__version__ = "1.6.dev0"
 
 
 # On OSX, we can get a runtime error due to multiple OpenMP libraries loaded