Ubuntu Plans For Python 3 By Default For Ubuntu 16.04 LTS

[Ansla]

Scons was another important Python project that previously claimed they have no plans for moving to Python 3 while now the port is in progress. It seems the time has finally come for Python 2 to be deprecated.

[rdnetto]

Python 3 has been a no go for many developers as large amounts of the Python ecosystem have been Python 2.x exclusive.

Super big popular Python related projects like Apache Spark, for example, simply won't work with Python 3. And they will tell you, the community they serve is mostly on 2.x

System Python and Server Side / Science Python do have very different communities.

Mercurial is still in Python 2 with no plans of porting as well.

The problem is that they made breaking changes in a language where duck typing is the norm. Normally when a language makes breaking changes, you get compiler errors, or even just warnings for using deprecated features. But the fundamental design of Python makes it quite hard to detect code which will behave differently. (Static analysers do exist, but they can't come close to what a language with static typing offers.)

The end result of this is that while Python 3 is a much better language for new projects, the effort required to port to it is simply not worth it.

[TheBlackCat]

Mercurial is still in Python 2 with no plans of porting as well.

Judging by recent commits, porting is not only planned, but being actively worked on.