new package: py-aspy-yaml (#13591)

* new package: py-aspy-yaml

* add python version dependency

var/spack/repos/builtin/packages/py-aspy-yaml/package.py

@@ -0,0 +1,19 @@
+# Copyright 2013-2019 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 PyAspyYaml(PythonPackage):
+    """Some extensions to pyyaml."""
+
+    homepage = "https://github.com/asottile/aspy.yaml/"
+    url      = "https://pypi.io/packages/source/a/aspy.yaml/aspy.yaml-1.3.0.tar.gz"
+
+    version('1.3.0', sha256='e7c742382eff2caed61f87a39d13f99109088e5e93f04d76eb8d4b28aa143f45')
+
+    depends_on('python@2.7:2.8,3.4:', type=('build', 'run'))
+    depends_on('py-setuptools', type='build')
+    depends_on('py-pyyaml',     type=('build', 'run'))