old_contents: import logging
  
  from benchbuild.projects.gentoo.gentoo import GentooGroup
  from benchbuild.utils.run import run, uchroot
  from plumbum import local
  
  
  class AutoPortage(GentooGroup):
      """
      Generic portage experiment.
      """
  
      def build(self):
          emerge_in_chroot = uchroot()["/usr/bin/emerge"]
          prog = self.DOMAIN + "/" + str(self.NAME)[len(self.DOMAIN) + 1:]
          with local.env(CONFIG_PROTECT="-*"):
              emerge_in_chroot("--autounmask-only=y",
                               "--autounmask-write=y",
                               prog,
                               retcode=None)
          run(emerge_in_chroot[prog])
  
      def run_tests(self, _):
          log = logging.getLogger('benchbuild')
          log.warn('Not implemented')
  
new_contents: import logging
  
  from benchbuild.projects.gentoo.gentoo import GentooGroup
  from benchbuild.utils.run import run, uchroot
  from plumbum import local
  
  
  class AutoPortage(GentooGroup):
      """
      Generic portage experiment.
      """
  
      def build(self):
          emerge_in_chroot = uchroot()["/usr/bin/emerge"]
          prog = self.DOMAIN + "/" + str(self.NAME)[len(self.DOMAIN) + 1:]
          with local.env(CONFIG_PROTECT="-*"):
              emerge_in_chroot("--autounmask-only=y",
                               "--autounmask-write=y",
                               prog,
                               retcode=None)
          run(emerge_in_chroot[prog])
  
      def run_tests(self, *args, **kwargs):
          log = logging.getLogger('benchbuild')
          log.warn('Not implemented')
  
subject: adjust to correct number of parameters