[tenfingers]

"python-bond" also came out in 2015: https://pypi.python.org/pypi/python-bond allows a simple interface between python runtimes and php/perl/nodejs.

[collyw]

There is a lot of overlap between these languages, and I wonder what any of them can do that can't be done in pure Python.

[tenfingers]

It's not much about language, it's mostly about code/ecosystem re-use (that is: if you have a library available in system X and you're writing for Y you can still take advantage of it).