Create Python Bindings

[platinumxy]

Summary

Create a python module with bindings into CoBRA that can be published to PyPi. Introduce: Python mappings into CoBRA's existing Exprs (using nanobind), expose some functions to allow for parsing strings to and from Exprs and introduce a reducer function that uses CoBRA to simplify expressions.

Architecture

lib/bindings/python
    CobraPython.cpp           - All code required to expose functions and classes to python
    CobraPython.h
    PythonInterface.cpp       - Code that implements all the bindings (i.e. str <-> expr ) 
    PythonInterface.h 
    pyproject.toml            - Configuration required for pypi deployment 

Python interface

• PyExpr class that mimics that of Expr.h to make conversion trivial, we want to hide the specifics of requiring a seprate list to store the variable for equation re-construction hence we need a minimal wrapper around the Expr class.

• to_expr(expr_string, max_vars=16) function to converts a provided string to an Expr in a similar manor to the cli's ParseToAst (This feels like something that should be re-factored into some form of shared library instead of being just in the CLI).

• reduce(expr, bitwidth=64) runs the reduction on the expression, we can have it accept a string or a Expr to avoid creating code that looks like reduce(to_expr(foo)).

• verify(original_expr, new_expr) using an optional dependency of Z3 (If were not forcing users to compile from source on pip install we should be ok here anyway?).

• Some misc functions to interact with and modify an Expr.

Tasks

• Update CMAKE to support building the python lib
• Investigate the z3 and other general requirements for pypi distribution
• Implement python Expr
• Implement conversions to and from pythons Expr to CoBRAs
• Create reduction and verification interface
• Add some methods and attributes to Expr to make them easier to work with
• Test, test and test