Release Notes for 1.9 - sympy/sympy Wiki

These are the release notes for SymPy 1.9. You can also find release notes for previous versions.

SymPy 1.9 was released on 9th October 2021

This version of SymPy has been tested on Python 3.6, 3.7, 3.8, 3.9, 3.10 and PyPy. See our Python version support policy for more information on when we plan to drop support for older Python versions.

Note in particular that SymPy 1.5.1 was the last release to support Python 2.7. SymPy 1.9 will not work on Python 2.7. Python 2.7 users should install SymPy 1.5.1 and will not be able to install any further SymPy updates without updating to Python 3.

Install SymPy with

pip install -U sympy

or if you use Anaconda

conda install sympy


There are many changes in 1.9 (see below).

Backwards compatibility breaks and deprecations

Please manually add any backwards compatibility breaks or deprecations here, in addition to the automatic listing below.

There are a number of changes and deprecations listed below. Most of these are really internal changes but they are listed here because in some cases it is hard to know if e.g. a downstream library has subclassed a SymPy class and modified its internals in an unexpected way. Few of the changes affect documented usage of SymPy.