If you work with strings in your Python scripts and you're writing obscure logic to process them, then you need to look into ...

flynt is a command line tool to automatically convert a project's Python code from old "%-formatted" and .format(...) strings into Python 3.6+'s "f-strings". Flynt will modify the files it runs on.

SmartCalculator is a small desktop calculator written in C++ using Qt and CMake. It supports parsing and evaluating mathematical expressions via a custom parser and generates an AST for expressions.