SymPy is a Python library for symbolic mathematics. It aims to become a full-featured computer algebra system (CAS) while keeping the code as simple as possible in order to be comprehensible and easily extensible. SymPy is written entirely in Python and does not require any external libraries. Optional dependencies are pyglet (needed only for plotting) and ipython. Please read the release notes at https://github.com/sympy/sympy/wiki/_pages for any backward compatibility issues.