old_contents: import re
  
  from django.core import validators
  
  
  class URLValidator(validators.URLValidator):
      """Custom url validator to include git urls and urls with http+ like prefixes
      """
      regex = re.compile(
          r'^(?:(?:(?:(?:http|git|hg|rechttp)\+)?'    # optional http+ or git+ or hg+
          r'(?:http|ftp|)s?|git)://|git@)'  # http:// or https:// or git:// or git@
          r'(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+(?:[A-Z]{2,6}\.?|[A-Z0-9-]{2,}\.?)|'  # domain...
          r'localhost|'  # localhost...
          r'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}|'  # ...or ipv4
          r'\[?[A-F0-9]*:[A-F0-9:]+\]?)'  # ...or ipv6
          r'(?::\d+)?'  # optional port
          r'(?:/?|[/?:]\S+)' # slash or question mark or just : followed by uri
          r'$', re.IGNORECASE)
  
      def __call__(self, value):
          super(URLValidator, self).__call__(value)
  
new_contents: import re
  
  from django.core import validators
  
  
  class URLValidator(validators.URLValidator):
      """Custom url validator to include git urls and urls with http+ like prefixes
      """
      regex = re.compile(
          r'^(?:(?:(?:(?:http|git|hg|rechttp|feed|rss|atom)\+)?'    # optional http+ or git+ or hg+
          r'(?:http|ftp|)s?|git)://|git@)'  # http:// or https:// or git:// or git@
          r'(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+(?:[A-Z]{2,6}\.?|[A-Z0-9-]{2,}\.?)|'  # domain...
          r'localhost|'  # localhost...
          r'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}|'  # ...or ipv4
          r'\[?[A-F0-9]*:[A-F0-9:]+\]?)'  # ...or ipv6
          r'(?::\d+)?'  # optional port
          r'(?:/?|[/?:]\S+)' # slash or question mark or just : followed by uri
          r'$', re.IGNORECASE)
  
      def __call__(self, value):
          super(URLValidator, self).__call__(value)
  
subject: Allow feed, rss, and atom prefixes in URL validator.