title: How to produce JSON with sorted keys in Go?
body: <p>In python you can produce JSON with keys in sorted order by doing</p>
  
  <pre><code>import json
  print json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4, separators=(',', ': '))
  </code></pre>
  
  <p>I have not found a similar option in Go. Any ideas how I can achieve similar behavior in go?</p>