SymPy is a team project and it was developed by a lot of people.
Here is a list of contributors together with what they do, (and in some cases links to their wiki pages), where they describe in more details what they do and what they are interested in (some people didn’t want to be mentioned here, so see our repository history for a full list).
Up-to-date list in the order of the first contribution is given in the AUTHORS file.
You can find a brief history of SymPy in the README.
Unless stated otherwise, all files in the SymPy project, SymPy’s webpage (and wiki), all images and all documentation including this User’s Guide are licensed using the new BSD license:
Copyright (c) 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 SymPy Development Team
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
a. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
b. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
c. Neither the name of SymPy nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
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DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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