Repository: scikit-learn/scikit-learn
Pull request: [MRG] DOC: Add SLEP and Governance in Dev Docs
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Reference SLEP and Governance in Dev Docs as per #13268, also resuming work from #13634 which was closed on account of a messy rebase.

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Fixes #13268 and uses work from #13634 by cherry-picking (using `git cherry-pick`) the commits and changes suggested

#### What does this implement/fix? Explain your changes.
Reference SLEP and Governance in Dev Docs


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Problem statement:
reference SLEP and Governance in dev docs
the Scikit-Learn Enhancement Proposal is mentioned in the recently merged Governance document (doc/governance.rst), but nowhere else I can see. The Governance doc is only mentioned in About. These are both things new contributors should be aware of. We should add:
* SLEP and Scikit-learn Enhancment Proposal entries to doc/glossary.rst
* mention of SLEP and the Governance documents to doc/developers/contributing.rst

Hints from issue discussion:
Hi @jnothman , can I work on the above issue?

> Hi @jnothman , can I work on the above issue?

I actually started over this, @thegaribguy  can you please pick up another issue ?
@LakshKD I was about to raise a PR as I finished the issue, you could have commented here atleast to let us know if the issue was taken already.
> @LakshKD I was about to raise a PR as I finished the issue, you could have commented here atleast to let us know if the issue was taken already.

@thegaribguy  Go ahead and raise the PR, no problem. I commented after your comment as you were asking to work on this issue which didn't imply that you were about to raise a PR :-)
> Hi @jnothman , can I work on the above issue?

@thegaribguy  You were asking to work on it so just after this comment, I commented to let you know that I was working, but you can go ahead and raise the PR. From next time, Please make sure to write well mentioning clearly that whether you are asking something or already completed something and are just at the verge of raising a PR. 
@LakshKD Sure, thanks.
@LakshKD and @thegaribguy don't seem to be active on this issue, so I made the PR, I hope that's okay @jnothman

Commit message: Remove trailing underscores

Patch to review:
diff --git a/doc/developers/contributing.rst b/doc/developers/contributing.rst
index b2987bbea7c83..0ea5e25933c1e 100644
--- a/doc/developers/contributing.rst
+++ b/doc/developers/contributing.rst
@@ -40,6 +40,10 @@ ticket to the
 `GitHub issue tracker <https://github.com/scikit-learn/scikit-learn/issues>`_. You are
 also welcome to post feature requests or pull requests.
 
+Governance
+----------
+The decision making process and governance structure of scikit-learn is laid
+out in the governance document: :ref:`governance`.
 
 Ways to contribute
 ==================
@@ -62,6 +66,13 @@ up" on issues that others reported and that are relevant to you.  It also helps
 us if you spread the word: reference the project from your blog and articles,
 link to it from your website, or simply star to say "I use it":
 
+In case a contribution/issue involves changes to the API principles
+or changes to dependencies or supported versions, it must be backed by a
+:ref:`slep`, where a SLEP must be submitted as a pull-request to
+`enhancement proposals <https://scikit-learn-enhancement-proposals.readthedocs.io>`_
+using the `SLEP template <https://scikit-learn-enhancement-proposals.readthedocs.io/en/latest/slep_template.html>`_
+and follows the decision-making process outlined in the governance document: :ref:`governance`.
+
 .. raw:: html
 
    <a class="github-button" href="https://github.com/scikit-learn/scikit-learn"
diff --git a/doc/glossary.rst b/doc/glossary.rst
index 99d0b5df03a75..ca1499a7e5801 100644
--- a/doc/glossary.rst
+++ b/doc/glossary.rst
@@ -675,6 +675,19 @@ General Concepts
         but not maintained by the core developer team.
         See https://scikit-learn-contrib.github.io.
 
+    scikit-learn enhancement proposals
+    SLEP
+    SLEPs
+        Changes to the API principles and changes to dependencies or supported
+        versions happen via a :ref:`SLEP <slep>` and follows the
+        decision-making process outlined in the :ref:`governance document <governance>`.
+        For all votes, a proposal must have been made public and discussed before the
+        vote. Such proposal must be a consolidated document, in the form of a
+        ‘Scikit-Learn Enhancement Proposal’ (SLEP), rather than a long discussion on an
+        issue. A SLEP must be submitted as a pull-request to
+        `enhancement proposals <https://scikit-learn-enhancement-proposals.readthedocs.io>`_ using the
+        `SLEP template <https://scikit-learn-enhancement-proposals.readthedocs.io/en/latest/slep_template.html>`_.
+
     semi-supervised
     semi-supervised learning
     semisupervised
diff --git a/doc/governance.rst b/doc/governance.rst
index d7d86f2b782fd..833d2ae3346cc 100644
--- a/doc/governance.rst
+++ b/doc/governance.rst
@@ -127,5 +127,5 @@ For all votes, a proposal must have been made public and discussed before the
 vote. Such proposal must be a consolidated document, in the form of a
 ‘Scikit-Learn Enhancement Proposal’ (SLEP), rather than a long discussion on an
 issue. A SLEP must be submitted as a pull-request to
-`scikit-learn/enhancement_proposals <https://github.com/scikit-learn/enhancement_proposals/>`_
-using the `SLEP template <https://github.com/scikit-learn/enhancement_proposals/blob/master/slep_template.rst>`_.
+`enhancement proposals <https://scikit-learn-enhancement-proposals.readthedocs.io>`_
+using the `SLEP template <https://scikit-learn-enhancement-proposals.readthedocs.io/en/latest/slep_template.html>`_.


Code review comments:
diff_hunk: @@ -675,6 +675,19 @@ General Concepts
         but not maintained by the core developer team.
         See https://scikit-learn-contrib.github.io.
 
+    scikit-learn enhancement proposals
+    SLEP
+    SLEPs
+        Changes to the API principles and changes to dependencies or supported
+        versions happen via a :ref:`SLEP <slep>` and follows the
+        decision-making process outlined in the :ref:`governance document <governance>`.
path: doc/glossary.rst
text: @user1:
```suggestion
        decision-making process outlined in :ref:`governance`.
```

diff_hunk: @@ -62,6 +66,13 @@ up" on issues that others reported and that are relevant to you.  It also helps
 us if you spread the word: reference the project from your blog and articles,
 link to it from your website, or simply star to say "I use it":
 
+In case a contribution/issue involves changes to the API principles
+or changes to dependencies or supported versions, it must be backed by a
+:ref:`slep`, where a SLEP must be submitted as a pull-request to
+`enhancement proposals <https://scikit-learn-enhancement-proposals.readthedocs.io>`_
+using the `SLEP template <https://scikit-learn-enhancement-proposals.readthedocs.io/en/latest/slep_template.html>`_
+and follows the decision-making process outlined in the governance document: :ref:`governance`.
path: doc/developers/contributing.rst
text: @user1:
```suggestion
and follows the decision-making process outlined in :ref:`governance`.
```
should suffice