docs: def normalize_route(route: str) -> str:
      """Strip some of the ugly regexp characters from the given pattern.
  
      >>> normalize_route('^/user/<user_id:int>/?$')
      u'/user/(user_id:int)/'
      """
      normalized_route = str(route).lstrip('^').rstrip('$').rstrip('?')
      normalized_route = normalized_route.replace('<', '(').replace('>', ')')
      return normalized_route