PyLuaTeX allows you to execute Python code and to include the resulting output in your LaTeX documents in a single compilation run. LaTeX documents must be compiled with LuaLaTeX for this to work. PyLuaTeX runs a Python InteractiveInterpreter (actually several if you use different sessions) in the background for on-the-fly code execution. Python code from your LaTeX file is sent to the background interpreter through a TCP socket. This approach allows your Python code to be executed and the output to be integrated in your LaTeX file in a single compilation run.