text: import 'core-js/features/promise';
  import "regenerator-runtime/runtime";
  import urljoin from 'url-join';
  import qs from 'qs';
  import Base64 from 'crypto-js/enc-base64';
  
  export function create_url(base_url, query_obj) {
      return urljoin(base_url, serialize_params(query_obj));
  }
  
  export function serialize_params(obj) {
      return "?" + qs.stringify(obj)
  }
  
  export function base64URL(string) {
      return string.toString(Base64).replace(/=/g, '').replace(/\+/g, '-').replace(/\//g, '_')
  }