If you program in Python on Windows, you know that there are a variety of versions of Python. Version 2.7 is still the standard, but the 3.x versions are probably getting better. You also need to worry about whether you are using 32-bit or 64-bit Python. Whenever you want to install a library, you need to be sure to get the library version that matches your Python version. That’s impossible half the time if you are using the standard package download site, whatever that may be. The developers of the library may or may not offer your version. If they don’t use your version and can’t be troubled with testing all the versions, then they won’t offer it.

The best work-around that I’ve found is a site by Christoph Gohlke. He offers unofficial Windows binaries for Python packages. There, you will typically find the version of the package that matches your Python version. Usually 32-bit and 64-bit options are available for recent releases of Python. Be sure to check there if you ever need a hard-to-find version of a package. It’s way easier than building it yourself.