PEP 421: Retain as bullet points

Author: hugovk

peps/pep-0421.rst

@@ -463,6 +463,9 @@ References
 .. [#ironpython] Feedback from the IronPython developers:
    https://mail.python.org/pipermail/ironpython-users/2012-May/015980.html
 
+* (2009) Dino Viehland offers his opinion:
+  https://mail.python.org/pipermail/python-dev/2009-October/092894.html
+
 .. [#jeff_hardy_2012] (2012) Jeff Hardy offers his opinion:
    https://mail.python.org/pipermail/ironpython-users/2012-May/015981.html
 
@@ -476,13 +479,23 @@ References
    https://mail.python.org/pipermail/pypy-dev/2012-May/009884.html
 
 .. [#guess] The ``platform`` code which divines the implementation name:
-   http://hg.python.org/cpython/file/2f563908ebc5/Lib/platform.py#l1247
+   https://hg.python.org/cpython/file/2f563908ebc5/Lib/platform.py#l1247
+
+* The original implementation of the cache tag in CPython:
+  https://hg.python.org/cpython/file/2f563908ebc5/Python/import.c#l121
+
+* Examples of implementation-specific handling in test.support:
+
+  * https://hg.python.org/cpython/file/2f563908ebc5/Lib/test/support.py#l509
+  * https://hg.python.org/cpython/file/2f563908ebc5/Lib/test/support.py#l1246
+  * https://hg.python.org/cpython/file/2f563908ebc5/Lib/test/support.py#l1252
+  * https://hg.python.org/cpython/file/2f563908ebc5/Lib/test/support.py#l1275
 
 .. [#os_name] The standard library entry for os.name:
    http://docs.python.org/3.3/library/os.html#os.name
 
 .. [#javatest] The use of ``os.name`` as 'java' in the stdlib test suite.
-   http://hg.python.org/cpython/file/2f563908ebc5/Lib/test/support.py#l512
+   https://hg.python.org/cpython/file/2f563908ebc5/Lib/test/support.py#l512
 
 .. [#Alyssa] Alyssa (Nick) Coghlan's proposal for ``sys.implementation.metadata``:
    https://mail.python.org/pipermail/python-ideas/2012-May/014984.html
@@ -492,9 +505,9 @@ References
 
 .. _issue #14673: http://bugs.python.org/issue14673
 
-.. _Lib/test/support.py: http://hg.python.org/cpython/file/2f563908ebc5/Lib/test/support.py
+.. _Lib/test/support.py: https://hg.python.org/cpython/file/2f563908ebc5/Lib/test/support.py
 
-.. _Python/import.c:  http://hg.python.org/cpython/file/2f563908ebc5/Python/import.c
+.. _Python/import.c:  https://hg.python.org/cpython/file/2f563908ebc5/Python/import.c
 
 
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