code: def get_mapping(repo, content_type):
      
      try:
          with open(
              os.path.join(repo.working_dir,
                           '_mappings',
                           '%s.json' % (content_type,)), 'r') as fp:
              return json.load(fp)
      except IOError:
          raise NotFound('Mapping does not exist.')
docs: Return an ES mapping for a content type in a repository.
  
      :param Repo repo:
          This git repository.
      :returns: dict