* line 446 of \/lib\/external\/classes\/external_api.php: core\\exception\\invalid_response_exception thrown
* line ? of unknownfile: call to core_external\\external_api::clean_returnvalue()
* line 259 of \/lib\/external\/classes\/external_api.php: call to call_user_func()
* line 83 of \/lib\/ajax\/service.php: call to core_external\\external_api::call_external_function()
",
