To facilitate my research and perhaps help someone else out there, I develop a python package based around numerical ODE solvers (Runge-Kutta methods, multistep methods, etc.) as objects. The package is called nodepy, and has somewhat limited functionality. However, it contains a very nice implementation of rooted trees, including the ability to compute all the things necessary for deriving order conditions of general linear methods. It also has a lot of nice functionality for Runge-Kutta methods, including a lot of things related to low-storage methods and embedded methods.
As of today, the package is finally available on the PyPI server, and therefore can be installed using
Hopefully this will encourage interested parties to try it out (or better yet, to contribute!)