I think the biggest thing, for me is Cython. I've not seen anything quite like it in other languages. It allows you to compile python code to c, with gradual typing. It also allows you to write c code inline w/ your python or interface with other C/C++ libraries. https://cython.org/ Other languages will be pressed to beat its utility (esp in the scientific computing world)
pybind11 is a modern version of the Boost Python approach to Python bindings. Header only and can be installed trivially from PyPi.
I like it well enough that I even use it for binding C code. Especially because it has nice numpy array support (albeit a little underdocumented).
(In general, the Boost C++ libraries are well-renowned in the C++ world.)