New package: py-uvw (#17719)

* py-uvw: added package for versions 0.0.7 and 0.3.1

* py-uvw: added py-setuptools as dependency

var/spack/repos/builtin/packages/py-uvw/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 PyUvw(PythonPackage):
+    """
+    UVW is a small utility library to write VTK files
+    from data contained in Numpy arrays.
+    """
+
+    homepage = "https://github.com/prs513rosewood/uvw"
+    url      = "https://pypi.io/packages/source/u/uvw/uvw-0.3.1.tar.gz"
+
+    maintainers = ['prs513rosewood']
+
+    version('0.3.1', sha256='31e3347ec342bd5381091f3c782ea1a1bfa4709d1de41cd700509e0b813f2265')
+    version('0.0.7', sha256='4bcb77cf9655f0dcd5f38f024210ac5ad7ebc6fcfb45f898468d29a927bcb7a5')
+
+    variant('mpi', description="Use parallel writers", default=False)
+
+    depends_on('python@3:', type=('build', 'run'))
+    depends_on('py-setuptools', type='build')
+    depends_on('py-numpy', type=('build', 'run'))
+    depends_on('py-mpi4py', type=('build', 'run'), when="+mpi")