General flowchart of the OneCovariance code. The green boxes indicate files that are fed to the code (visit the readthedocs webpage, https://onecovariance.readthedocs.io/en/latest/index.html, for a more detailed discussion). The dashed lines with arrows indicate that files or functionalities are included, but not inherited. The solid arrows instead indicate inheritance. Each blue box indicates a python module in the form of a class with the corresponding name. The red box is a C++ class wrapped into python with pybind to carry out some of the heavy lifting in the code. Section numbers indicate where the corresponding equations and description of the content of each module can be found in the paper.