The PEP doesn't specify any of the API changes for Python 2.7. I feel it is necessary for the PEP to show a few typical code snippets using urllib in Python 2.7 and how one would modify these in order to disable the cert checking.
There are also a few typos; especially this paragraph puzzled me:
This will be acheived by adding a new ``ssl._create_default_https_context``
function, which is the same as ``ssl.create_default``. ``http.client`` can then
replace it's usage of ``ssl._create_stdlib_context`` with the new
``ssl._create_default_https_context``.