title: what is _interopRequireDefault ?
body: <p>I have seen an explanation on <a href="http://2ality.com" rel="noreferrer">this website</a> that say : </p>
  
  <blockquote>
    <p>_interopRequireDefault(): An ES6 CommonJS module is used as is (if it has a default export then it has a property named default). A normal
    CommonJS module becomes the value of the property default. In other
    words, in the later case, the module’s exports become the default
    export.</p>
  </blockquote>
  
  <p>In codes, there is often several <code>_interopRequireDefault</code> written in. </p>
  
  <p>So if I understand well, since default export is a bunch of key/value on the whole file exported as a total entity, <code>_interopRequireDefault</code> allows to choose which modules will enter in the default export of a specific code that it ? </p>