write declaration file for extended class by typescript decorator

is It possible to write declaration file (.d.ts) for methods
that extended by typescript decorator ( Delete All In Example Below)
in order to give vs code ability for intillisense .

const classExtender = (target:any) => {
  target.DeleteAll = function() {
      //Some code
  return target;

class baseClass{
  foo() {

Source: Angular Questions