Every programming language has its benefits and its drawbacks. Python, for example, provides a dynamic and clean environment for the developer, which boosts productivity by hiding much of the “dirty work”: memory management, type inference (duck typing, in this case), and more. Such benefits usually come at the cost of efficiency, which is something that other programming languages (such as C++) excel in.
The next logical step would then be a way to combine the benefits of such different programming languages in a single system. For instance, we could use C++ solely for the cpu-intensive parts, while the rest of the software could very well be written entirely in Python. The missing piece would then be a way to integrate the two. The common way of doing so is through SWIG, which is a tool that is able to wrap C++ to many different programming languages, Python included. Using SWIG right out of the box, we will be able to invoke C++ code directly from a Python interpreter. But what if we wanted to extend C++ classes in Python, making native C++ seamlessly call Python code?