new_contents: import contextlib
  import logging
  import subprocess
  
  LOGGER = logging.getLogger(__name__)
  
  def execute(command):
      LOGGER.debug("Executing %s", ' '.join(command))
      proc = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
      stdout, stderr = proc.communicate(input=None)
      LOGGER.debug("stdout %s", stdout)
      LOGGER.debug("stderr %s", stderr)
  
  @contextlib.contextmanager
  def stash():
      execute(['git', 'stash', '-u', '--keep-index'])
      yield
      execute(['git', 'reset', '--hard'])
      execute(['git', 'stash', 'pop', '--quiet', '--index'])
  
subject: Add git module