NOTE: PyPy is more mature and better supported now than it was in 2013, when this question was asked. Avoid drawing conclusions from out-of-date information. PyPy, as others have been quick to mention, has tenuous support for C extensions. It has support, but typically at slower-than-Python speeds and it’s iffy at best. Hence a lot … Read more
See the Wikipedia article on modular exponentiation. Basically, when you do a**d % n, you actually have to calculate a**d, which could be quite large. But there are ways of computing a**d % n without having to compute a**d itself, and that is what pow does. The ** operator can’t do this because it can’t … Read more
If you want to determine whether a value is exactly True (not just a true-like value), is there any reason to use if foo == True rather than if foo is True? If you want to make sure that foo really is a boolean and of value True, use the is operator. Otherwise, if the … Read more
Finally I found the solution myself, see the Docs: https://docs.python.org/3/installing/index.html?highlight=pip#work-with-multiple-versions-of-python-installed-in-parallel Just call: pythonXX -m pip install SomePackage That would work separately for each version of installed python. Also, according to the docs, if we want to do the same thing in windows, the command is a bit different: py -2 -m pip install SomePackage # … Read more