This PEP outlines the steps required to migrate Python's development process from Mercurial [3] as hosted at hg.python.org [1] to Git [4] on GitHub [2]
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The fate of hg.python.org
With the code repositories moving over to Git [4] , there is no technical need to keep hg.python.org [1] running. Having said that, some in the community would like to have it stay functioning as a Mercurial [3] mirror of the Git repositories. Others have said that they still want a mirror, but one using Git.
As maintaining hg.python.org is not necessary, it will be up to the PSF infrastructure committee to decide if they want to spend the time and resources to keep it running. They may also choose whether they want to host a Git mirror on PSF infrastructure.
Guido's last commit, in both the github repo and the mercurial repo.
https://github.com/python/cpython/commit/934aba66ef09e94422b...
https://hg.python.org/cpython/rev/3db1959c2c53
Someone sensible may be able to shed some light on it. Presumably there's a bridge between the two somewhere.