yangck/celery @ 5.0-devel

Ask Solem 8c3b680cad Merge branch '4.0' into 5.0-devel		%!s(int64=7) %!d(string=hai) anos
..
__init__.py	6fa86ebd28 Started on the next-steps tutorial	%!s(int64=12) %!d(string=hai) anos
celery.py	4a99648a08 Removes __future__ imports	%!s(int64=8) %!d(string=hai) anos
tasks.py	8c3b680cad Merge branch '4.0' into 5.0-devel	%!s(int64=7) %!d(string=hai) anos