old_contents: ##############################################################################
  # Copyright (c) 2013-2016, 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/llnl/spack
  # Please also see the LICENSE file 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 *
  import os
  
  
  class Libxml2(Package):
      """Libxml2 is the XML C parser and toolkit developed for the Gnome
         project (but usable outside of the Gnome platform), it is free
         software available under the MIT License."""
      homepage = "http://xmlsoft.org"
      url      = "http://xmlsoft.org/sources/libxml2-2.9.2.tar.gz"
  
      version('2.9.2', '9e6a9aca9d155737868b3dc5fd82f788')
  
      variant('python', default=False, description='Enable Python support')
  
      extends('python', when='+python', ignore=r'(bin.*$)|(include.*$)|(share.*$)|(lib/libxml2.*$)|(lib/xml2.*$)|(lib/cmake.*$)')
      depends_on('zlib')
      depends_on('xz')
  
      def install(self, spec, prefix):
          if '+python' in spec:
              site_packages_dir = os.path.join(prefix,
                                               'lib/python%s/site-packages'
                                               % (spec['python'].version.up_to(2)))
              python_args = ["--with-python=%s" % spec['python'].prefix,
                             "--with-python-install-dir=%s" % site_packages_dir]
          else:
              python_args = ["--without-python"]
  
          configure("--prefix=%s" % prefix,
                    *python_args)
  
          make()
          make("install")
  
new_contents: ##############################################################################
  # Copyright (c) 2013-2016, 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/llnl/spack
  # Please also see the LICENSE file 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 *
  import os
  
  
  class Libxml2(Package):
      """Libxml2 is the XML C parser and toolkit developed for the Gnome
         project (but usable outside of the Gnome platform), it is free
         software available under the MIT License."""
      homepage = "http://xmlsoft.org"
      url      = "http://xmlsoft.org/sources/libxml2-2.9.2.tar.gz"
  
      version('2.9.2', '9e6a9aca9d155737868b3dc5fd82f788')
  
      variant('python', default=False, description='Enable Python support')
  
      extends('python', when='+python', ignore=r'(bin.*$)|(include.*$)|(share.*$)|(lib/libxml2.*$)|(lib/xml2.*$)|(lib/cmake.*$)')
      depends_on('zlib')
      depends_on('xz')
  
      def install(self, spec, prefix):
          if '+python' in spec:
              site_packages_dir = os.path.join(prefix,
                                               'lib/python%s/site-packages' %
                                               (spec['python'].version.up_to(2)))
              python_args = ["--with-python=%s" % spec['python'].prefix,
                             "--with-python-install-dir=%s" % site_packages_dir]
          else:
              python_args = ["--without-python"]
  
          configure("--prefix=%s" % prefix,
                    *python_args)
  
          make()
          make("install")
  
subject: Fix flake8 error