运行import { ajax } from 'rxjs/ajax';时出现以下错误，
(node:8582) ExperimentalWarning: The ESM module loader is experimental.
file:///home/..../foo.mjs:1
import { ajax } from 'rxjs/ajax';
^^^^
SyntaxError: The requested module 'rxjs/ajax' does not provide an export named 'ajax'
at ModuleJob._instantiate (internal/modules/esm/module_job.js:79:21)