code: def http_auth_required(realm):
      
  
      def decorator(fn):
          @wraps(fn)
          def wrapper(*args, **kwargs):
              if _check_http_auth():
                  return fn(*args, **kwargs)
              if _security._unauthorized_callback:
                  return _security._unauthorized_callback()
              else:
                  r = _security.default_http_auth_realm \
                      if callable(realm) else realm
                  h = {'WWW-Authenticate': 'Basic realm="%s"' % r}
                  return _get_unauthorized_response(headers=h)
          return wrapper
  
      if callable(realm):
          return decorator(realm)
      return decorator
docs: Decorator that protects endpoints using Basic HTTP authentication.
  
      :param realm: optional realm name