Numba

Numba is an open-source JIT compiler that translates a subset of Python and NumPy into fast machine code using LLVM, via the llvmlite Python package. It offers a range of options for parallelising Python code for CPUs and GPUs, often with only minor code changes.

Numba was started by Travis Oliphant in 2012 and has since been under active development at its repository in GitHub with frequent releases. The project is driven by developers at Anaconda, Inc., with support by DARPA, the Gordon and Betty Moore Foundation, Intel, Nvidia and AMD, and a community of contributors on GitHub.

Example
Numba can be used by simply applying the  decorator to a Python function that does numerical computations:

The just-in-time compilation happens transparently when the function is called:

Numba's website contains many more examples, as well as information on how to get good performance from Numba.

GPU support
Numba can compile Python functions to GPU code. Initially two backends are available:

Since release 0.56.4, AMD ROCm HSA has been officially moved to unmaintained status and a separate repository stub has been created for it.
 * Nvidia CUDA, see https://numba.pydata.org/numba-doc/dev/cuda
 * AMD ROCm HSA, see https://numba.pydata.org/numba-doc/dev/roc

Alternative approaches
Numba is one approach to make Python fast, by compiling specific functions that contain Python and NumPy code. Many alternative approaches for fast numeric computing with Python exist, such as Cython, Pythran, and PyPy.