Python C API and global variables modified in python functions

The Python C API allows you to extend Python by writing C or C++ code that can be imported and used in Python programs. This tutorial will guide you through the process of creating a Python extension module using the Python C API. We will also cover how to modify global variables from Python functions written in C.
Before you begin, make sure you have the following installed:
To create a Python extension module, you need to write C code that defines functions and data structures, and then compile it into a shared library that Python can import. Here's a step-by-step guide with an example.
Let's create a simple C function that modifies a global variable in Python:
This code defines two functions, set_global and get_global, which can be called from Python. The global variable global_var is modified by set_global and retrieved by get_global.
To compile the C code, create a setup.py file with the following content:
Then, run the following command to build the module:
Now you can use your Python module in a Python script:
Running the script will print "The global variable is 42," as it sets and retrieves the global variable from your C code.
In this tutorial, you learned how to create a Python extension module using the Python C API and modify global variables from Python functions written in C. This is just a basic example, and you can extend this knowledge to build more complex and powerful Python extensions.
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