To support building for Apple ARM64 which was introduced in MacOS 11
OpenSSL added support for Apple ARM in 1.1.1
(61168b5b8d).
Python added support for MacOS 11 in 3.7.8+, 3.8.4+, 3.9.0+
(https://github.com/python/cpython/pull/21113 and backports).
* Update PyPy download links. Remove releases that are no longer available.
PyPy has moved from bitbucket.org to foss.heptapod.net.
Downloads have moved to https://downloads.python.org/pypy/; some of the archives are no longer available.
Portable PyPy has moved from bitbucket.org to Github. Old archives have been moved to a 3rd-party "Bitbucket Archive" site.
* Update Stackless download links. Remove releases that are no longer available.
Stackless has moved from Bitbucket to Github. Old downloads have been renamed(?); stackless.com no longer works via HTTPS.
* Delete releases that have become invalid since the last check
* fix changed checksums
OS X arm64 will be installed with Python 3.9 only. Other versions bundled with python 3.8. Miniforge does not have as wide a choice of python versions as miniconda.
The Python version is specific only to the base environment.