text: import {writeToBody} from './WriteToBody.js';
  
  const observer = {
      next: i => writeToBody(`interval ${i}`),
      error: err => writeToBody(`error: ${err}` ),
      complete: msg => writeToBody(`Completed`)
  }
  
  const observable = observer => {
  
      let i = 0;
  
      let intervalId = setInterval(() => {
  
          observer.next(i);
          i++;
      }, 1000);    
  }
  
  observable(observer);
  