title: Set environment variable with shelljs
body: <p>I'm trying to set an env variable in node with shelljs</p>
  
  <p>so here's the psudo code:</p>
  
  <pre><code>const shell = require('shelljs');
  
  shell.exec('export MM=2');
  shell.exec('echo $MM');
  </code></pre>
  
  <p>but  this does not printout the value of <code>MM</code></p>
  
  <p>Any suggestions on how to set an env variable through node with <code>export</code> (execute bash command)?</p>