You're free to try and see if the code also works in Python3.
Python3 used to come without a lot of the "batteries" that make Python a useful language for science-y stuff (numpy, matplotlib, Cython),and the 'improvements' that Python3 brings are not big enough that people would switch over.
Contrast this to C++11, which brings real improvements to pain points that existed before (i.e., areas of the STL that ought to have been standardized but were not).
Contrast this to Java 6 (Generics) and Java 8 (Lambdas) which solve actual perceived pain points that many people who program in Java are feeling.
The biggest pain point in Python2-the-language isn't any missing language feature -- most people are happy with those since at least 2.6. Instead, it's speed, and people are indeed transitioning part of their programs from Python2 to Cython. Python3 doesn't do anything for speed.
Python3 used to come without a lot of the "batteries" that make Python a useful language for science-y stuff (numpy, matplotlib, Cython),and the 'improvements' that Python3 brings are not big enough that people would switch over.
Contrast this to C++11, which brings real improvements to pain points that existed before (i.e., areas of the STL that ought to have been standardized but were not).
Contrast this to Java 6 (Generics) and Java 8 (Lambdas) which solve actual perceived pain points that many people who program in Java are feeling.
The biggest pain point in Python2-the-language isn't any missing language feature -- most people are happy with those since at least 2.6. Instead, it's speed, and people are indeed transitioning part of their programs from Python2 to Cython. Python3 doesn't do anything for speed.