text: ##############################################################################
  # Copyright (c) 2013-2017, Lawrence Livermore National Security, LLC.
  # Produced at the Lawrence Livermore National Laboratory.
  #
  # This file is part of Spack.
  # Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
  # LLNL-CODE-647188
  #
  # For details, see https://github.com/spack/spack
  # Please also see the NOTICE and LICENSE files for our notice and the LGPL.
  #
  # This program is free software; you can redistribute it and/or modify
  # it under the terms of the GNU Lesser General Public License (as
  # published by the Free Software Foundation) version 2.1, February 1999.
  #
  # This program is distributed in the hope that it will be useful, but
  # WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
  # conditions of the GNU Lesser General Public License for more details.
  #
  # You should have received a copy of the GNU Lesser General Public
  # License along with this program; if not, write to the Free Software
  # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  ##############################################################################
  from spack import *
  
  
  class PyTornado(PythonPackage):
      """Tornado is a Python web framework and asynchronous networking
      library."""
      homepage = "https://github.com/tornadoweb/tornado"
      url      = "https://github.com/tornadoweb/tornado/archive/v4.4.0.tar.gz"
  
      version('4.4.0', 'c28675e944f364ee96dda3a8d2527a87ed28cfa3')
  
      depends_on('py-setuptools', type='build')
  
      # requirements from setup.py
      # These dependencies breaks concretization
      # See https://github.com/spack/spack/issues/2793
      # depends_on('py-backports-ssl-match-hostname', when='^python@:2.7.8', type=('build', 'run'))  # noqa
      # depends_on('py-singledispatch', when='^python@:3.3', type=('build', 'run'))  # noqa
      # depends_on('py-certifi', when='^python@:3.3', type=('build', 'run'))
      # depends_on('py-backports-abc@0.4:', when='^python@:3.4', type=('build', 'run'))  # noqa
      depends_on('py-backports-ssl-match-hostname', type=('build', 'run'))
      depends_on('py-singledispatch', type=('build', 'run'))
      depends_on('py-certifi', type=('build', 'run'))
      depends_on('py-backports-abc@0.4:', type=('build', 'run'))
  