method Timeout.prototype.ref
          
Usage in Deno
import { Timeout } from "node:timers";
Timeout.prototype.ref(): this 
      When called, requests that the Node.js event loop not exit so long as theTimeout is active. Calling timeout.ref() multiple times will have no effect.
By default, all Timeout objects are "ref'ed", making it normally unnecessary
to call timeout.ref() unless timeout.unref() had been called previously.
this
      
    a reference to timeout