title: How to return certain keys from an object
body: <p>this is my object:</p>
  
  <pre><code>a={"a":"1","b":"2","c":"3","d":"4","e":"5","f":"6"}
  </code></pre>
  
  <p>This returns all the keys:</p>
  
  <pre><code>Object.keys(a)
  ["a", "b", "c", "d", "e", "f"]
  </code></pre>
  
  <p>This returns all the keys except 'a':</p>
  
  <pre><code>Object.keys(a).filter(function(k) {return k !== 'a'})
  ["b", "c", "d", "e", "f"]
  </code></pre>
  
  <p>how can I return all keys except 1 or more keys for example <code>a</code> or <code>b</code> or <code>c</code>?</p>
  
  <p>I have tried a few permutations but can't seem to get it, 1 below, or maybe it's not possible this way?</p>
  
  <pre><code>Object.keys(a).filter(function(k) {return k !== ('a','b')})
  ["a", "c", "d", "e", "f"]
  </code></pre>