old_contents: """
  Middleware for injecting the live-reload script.
  """
  from bs4 import BeautifulSoup
  
  from django.utils.encoding import smart_str
  from livereload import livereload_port
  
  
  class LiveReloadScript(object):
      """
      Inject the live-reload script into your webpages.
      """
  
      def process_response(self, request, response):
          content_type = response.get(
              'Content-Type', '').split(';')[0].strip().lower()
          if content_type not in ['text/html', 'application/xhtml+xml']:
              return response
  
          soup = BeautifulSoup(
              smart_str(response.content),
              'html.parser',
          )
  
          if not getattr(soup, 'head', None):
              return response
  
          script = soup.new_tag(
              'script', src='http://localhost:%d/livereload.js' % livereload_port(),
          )
          soup.head.append(script)
  
          response.content = str(soup)
  
          return response
  
new_contents: """
  Middleware for injecting the live-reload script.
  """
  from bs4 import BeautifulSoup
  
  from django.utils.encoding import smart_str
  from django.conf import settings
  from livereload import livereload_port
  
  
  class LiveReloadScript(object):
      """
      Inject the live-reload script into your webpages.
      """
  
      def process_response(self, request, response):
          content_type = response.get('Content-Type', '').split(';')[0].strip().lower()
          if content_type not in ['text/html', 'application/xhtml+xml'] or settings.DEBUG == False:
              return response
  
          soup = BeautifulSoup(
              smart_str(response.content),
              'html.parser',
          )
  
          if not getattr(soup, 'head', None):
              return response
  
          script = soup.new_tag(
              'script', src='http://localhost:%d/livereload.js' % livereload_port(),
          )
          soup.head.append(script)
  
          response.content = str(soup)
  
          return response
  
subject: Update middleware.py