code: def get_mailcap_entry(self, url):
          
  
          for parser in mime_parsers.parsers:
              if parser.pattern.match(url):
                  # modified_url may be the same as the original url, but it
                  # could also be updated to point to a different page, or it
                  # could refer to the location of a temporary file with the
                  # page's downloaded content.
                  try:
                      modified_url, content_type = parser.get_mimetype(url)
                  except Exception as e:
                      # If Imgur decides to change its html layout, let it fail
                      # silently in the background instead of crashing.
                      _logger.warning('parser %s raised an exception', parser)
                      _logger.exception(e)
                      raise exceptions.MailcapEntryNotFound()
                  if not content_type:
                      _logger.info('Content type could not be determined')
                      raise exceptions.MailcapEntryNotFound()
                  elif content_type == 'text/html':
                      _logger.info('Content type text/html, deferring to browser')
                      raise exceptions.MailcapEntryNotFound()
  
                  command, entry = mailcap.findmatch(
                      self._mailcap_dict, content_type, filename=modified_url)
                  if not entry:
                      _logger.info('Could not find a valid mailcap entry')
                      raise exceptions.MailcapEntryNotFound()
  
                  return command, entry
  
          # No parsers matched the url
          raise exceptions.MailcapEntryNotFound()
docs: Search through the mime handlers list and attempt to find the
          appropriate command to open the provided url with.
  
          Will raise a MailcapEntryNotFound exception if no valid command exists.
  
          Params:
              url (text): URL that will be checked
  
          Returns:
              command (text): The string of the command that should be executed
                  in a subprocess to open the resource.
              entry (dict): The full mailcap entry for the corresponding command