new package: py-pycosat (#15225)

var/spack/repos/builtin/packages/py-pycosat/package.py

+# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+from spack import *
+
+
+class PyPycosat(PythonPackage):
+    """PicoSAT is a popular SAT solver written by Armin Biere in pure C. This
+    package provides efficient Python bindings to picosat on the C level, i.e.
+    when importing pycosat, the picosat solver becomes part of the Python
+    process itself. For ease of deployment, the picosat source (namely
+    picosat.c and picosat.h) is included in this project. These files have been
+    extracted from the picosat source (picosat-965.tar.gz)."""
+
+    homepage = "https://github.com/ContinuumIO/pycosat"
+    url      = "https://pypi.io/packages/source/p/pycosat/pycosat-0.6.3.zip"
+
+    version('0.6.3', sha256='4c99874946a7e939bb941bbb019dd2c20e6068e3107c91366e7779c69d70e0ed')