old_contents: # -*- coding: utf-8 -*-
  from django.conf import settings
  
  JS_VAR_NAME = getattr(settings, 'JS_REVERSE_JS_VAR_NAME', 'Urls')
  
  JS_AVAILABLE_NAMESPACES = getattr(settings, 'JS_REVERSE_AVAILABLE_NAMESPACES', [])
new_contents: # -*- coding: utf-8 -*-
  from __future__ import unicode_literals
  from django.conf import settings
  from django.utils.functional import lazy
  from six import text_type as str
  
  JS_VAR_NAME = lazy(
      lambda: str(getattr(settings, 'JS_REVERSE_JS_VAR_NAME', 'Urls')),
      str)()
  JS_AVAILABLE_NAMESPACES = lazy(
      lambda: getattr(settings, 'JS_REVERSE_AVAILABLE_NAMESPACES', []),
      list, tuple)()
  
subject: Use lazy objects for variables in .settings