  A freely available Python code for modelling SNR evolution has been created.
This software is intended for two purposes: to understand SNR evolution; and to
use in modelling observations of SNR for obtaining good estimates of SNR
properties. It includes all phases for the standard path of evolution for
spherically symmetric SNRs. In addition, alternate evolutionary models are
available, including evolution in a cloudy ISM, the fractional energy loss
model, and evolution in a hot low-density ISM. The graphical interface takes in
various parameters and produces outputs such as shock radius and velocity vs.
time, SNR surface brightness profile and spectrum. Some interesting properties
of SNR evolution are demonstrated using the program.
