Cython can be used to write Python extensions and interface with C/C++ code. It allows gradually adding C-like features to Python code. Cython code can be compiled to Python extensions and provide performance improvements over pure Python. OpenMP support in Cython allows releasing the GIL and performing parallel operations across threads to further improve performance of CPU-bound tasks. Benchmark results showed near-linear speedups from using 2-4 threads. However, using Cython and OpenMP requires more code and loses some Python safety, and requires knowledge of C in addition to Python.