code: def contributors(lancet, output):
      
      sorting = pygit2.GIT_SORT_TIME | pygit2.GIT_SORT_REVERSE
      commits = lancet.repo.walk(lancet.repo.head.target, sorting)
      contributors = ((c.author.name, c.author.email) for c in commits)
      contributors = OrderedDict(contributors)
  
      template_content = content_from_path(
          lancet.config.get('packaging', 'contributors_template'))
      template = Template(template_content)
      output.write(template.render(contributors=contributors).encode('utf-8'))
docs: List all contributors visible in the git history.