I do this all the time. I don't even write pseudo code sometimes, but the actual code I need before translating it over. I feel it keeps me in check and it's a great way for me to really get to understand the code I'm dealing with :)

SimpleFilter I wanted to build my own Python 3 module for creating kernels/filters and for easy image convolution (to create convolutional layers). This module is the infrastructure to a simple yet effective ML webapp I'm currently building called Ibis Vision.