title: validating JSON from command line using `python -m jsontool` gives 'No JSON object could be decoded'
body: <p>I have a <code>data.json</code> file that I'm validating through the command line using python's json.tool, but it keeps giving me back an error message:</p>
  
  <pre><code>$ python -m json.tool &lt; data.json
  No JSON object could be decoded
  </code></pre>
  
  <p>Here are the contents of <code>data.json</code>: </p>
  
  <pre><code>$ cat data.json
  { "fields": 
      [
          [ "first_name", null, {} ],
          [ "last_name", null, {} ],
          [ "addr1", null, {} ],
          [ "addr2", null, {} ],
          [ "city", null, {} ],
      ]
  }
  </code></pre>
  
  <p>I don't have a problem with <a href="https://stackoverflow.com/a/18415636/1094541">single quotes</a>, nor is the file empty (obviously), so I'm not sure what's causing the problem here. </p>