Also the following related changes:
* Removed Python 2 support because it's not supported by TF and related packages for a long time.
* Upgraded tensorboard and estimator packages to the required versions.
* Added extra plugins for tensorboard to support profiling.
* In the previous derivation versions, TF_SYSTEM_LIBS didn't have any effect because it was reset at repo fetching stage, so TF always used its own dependencies. Made TF_SYSTEM_LIBS actually work and fixed the errors caused by enabling it.
* Enabled tensorboard by default (but still keeping an option to disable it if needed).
Major breaking change from 1.x, so treating keeping both versions for now.
(adapted from 33f11be707e39acf96423f97f3baa80d8f11a0cb)
(adapted from 9e8dea7986dbdde850a58c7704182776642d8919)
Fix build after https://github.com/NixOS/nixpkgs/pull/56669. Update the
python2 hash and re-add the python2 `futures` dependency. Not sure if
there was a reason for it to be removed in the first place.
The `buildPython*` function computes name from `pname` and `version`.
This change removes `name` attribute from all expressions in
`pkgs/development/python-modules`.
While at it, some other minor changes were made as well, such as
replacing `fetchurl` calls with `fetchPypi`.
