Sage's Python wrapper for the PARI library, modified to stand alone.

License: All parts of this package are released under the GNU General
Public License, version 2 or (at your discretion) any later version as
published by the Free Software Foundation. Specifically:

* PARI/GP is Copyright (C) 2000-2013 by The PARI Group, Bordeaux, and
  released under GPL v2+ as per the README file in the included pari tarball.

* The Cython code is primary derived from Sage version 7.4 and is
  copyright 2012 by William Stein, Jeroen Demeyer et. al. and released
  under GPL v2+ as per

* The modifications are copyright 2012-present by Marc Culler and
  Nathan Dunfield and are hereby released under GPL v2+.

Please see 

for the complete license text.