docs: def convert(self, request, response, data):
          """
          Performs the desired formatting.
  
          :param request: The webob Request object describing the
                          request.
          :param response: The webob Response object describing the
                           response.
          :param data: The data dictionary list returned by the
                       prepare() method.
  
          :returns: A string, the results of which are the desired
                    conversion.
          """
  
          result = []
          for conv, datum in zip(self.conversions, data):
              # Only include conversion if it's allowed
              if conv.modifier.accept(response.status_code):
                  result.append(conv.convert(request, response, datum))
              else:
                  result.append('-')
  
          return ''.join(result)