old_contents: from hashlib import sha256
  import os
  from tambo import Transport
  import merfi
  from merfi import logger, util, base
  
  
  class Iso(base.BaseCommand):
      help_menu = 'simple ISO manipulation'
      _help = """
  A very simple interface to create ISOs with some sane defaults (like ensure
  source directory has proper read permissions).
  
  Default behavior will perform these actions on a source directory::
  
      genisoimage -r -o sourcedir-dvd.iso {source directory}
      sha256sum sourcedir-dvd.iso > sourcedir-dvd.iso.SHA256SUM
  
  %s
  
  Options:
  
  -o, --output      Custom filename output (defaults to '<sourcedir>-dvd.iso').
  
  Positional Arguments:
  
  [source directory]  The path to create the ISO from. Required with no defaults.
  """
      executable = 'genisoimage'
      name = 'iso'
  
      def parse_args(self, argv=None):
          """ pass argv during testing """
          if argv is None:
              argv = self.argv
          options = [['--output', '-o']]
          parser = Transport(argv, options=options)
          parser.catch_help = self.help()
          parser.parse_args()
          self.source = util.infer_path(parser.unknown_commands)
          self.output = parser.get('--output', self.source + '-dvd.iso')
          self.check_dependency()
          self.make_iso()
          self.make_sha256sum()
  
      def make_iso(self):
          cmd = ['genisoimage', '-r', '-o', self.output, self.source]
          util.run(cmd)
  
      def make_sha256sum(self):
          chsum = sha256()
          self.output_checksum = self.output + '.SHA256SUM'
          with open(self.output, 'rb') as f:
              for chunk in iter(lambda: f.read(4096), b""):
                  chsum.update(chunk)
          digest = chsum.hexdigest()
          with open(self.output_checksum, 'w') as chsumf:
              chsumf.write("%s  %s\n" % (digest, os.path.basename(self.output)))
  
new_contents: from hashlib import sha256
  import os
  from tambo import Transport
  from merfi import util, base
  
  
  class Iso(base.BaseCommand):
      help_menu = 'simple ISO manipulation'
      _help = """
  A very simple interface to create ISOs with some sane defaults (like ensure
  source directory has proper read permissions).
  
  Default behavior will perform these actions on a source directory::
  
      genisoimage -r -o sourcedir-dvd.iso {source directory}
      sha256sum sourcedir-dvd.iso > sourcedir-dvd.iso.SHA256SUM
  
  %s
  
  Options:
  
  -o, --output      Custom filename output (defaults to '<sourcedir>-dvd.iso').
  
  Positional Arguments:
  
  [source directory]  The path to create the ISO from. Required with no defaults.
  """
      executable = 'genisoimage'
      name = 'iso'
  
      def parse_args(self, argv=None):
          """ pass argv during testing """
          if argv is None:
              argv = self.argv
          options = [['--output', '-o']]
          parser = Transport(argv, options=options)
          parser.catch_help = self.help()
          parser.parse_args()
          self.source = util.infer_path(parser.unknown_commands)
          self.output = parser.get('--output', self.source + '-dvd.iso')
          self.check_dependency()
          self.make_iso()
          self.make_sha256sum()
  
      def make_iso(self):
          cmd = ['genisoimage', '-r', '-o', self.output, self.source]
          util.run(cmd)
  
      def make_sha256sum(self):
          chsum = sha256()
          self.output_checksum = self.output + '.SHA256SUM'
          with open(self.output, 'rb') as f:
              for chunk in iter(lambda: f.read(4096), b""):
                  chsum.update(chunk)
          digest = chsum.hexdigest()
          with open(self.output_checksum, 'w') as chsumf:
              chsumf.write("%s  %s\n" % (digest, os.path.basename(self.output)))
  
subject: remove unused imports