The implementation itself is relatively simple. The most popular Python implementation is Tom Cocagne's pysrp that builds on csrp, his original C implementation

The implementation itself is relatively simple. The most popular Python implementation is Tom Cocagne's pysrp that builds on csrp, his original C implementation: https://github.com/cocagne/pysrp https://github.com/cocagne/pysrp. I used this as a guide to write a pure Python3 implementation of SRP-6a some years ago that I needed for protocol testing on embedded devices, and to internalize how the algorithm worked and the complexity of the calculations: https://bitbucket.org/pbleyer/py3srp https://bitbucket.org/pbleyer/py3srp. That being said, I would never use plain vanilla Python for cryptography in a system that needs to be strongly secured. Too many side channel and timing attacks possible where you can replicate or estimate the state of things locally once you know the other side is running a Python VM.