title: jinja2 json template omiting <key : "value"> pair
body: <p>I am using jinja2 templating for rendering data in json </p>
  
  <p>I have python data as </p>
  
  <pre><code>name = ['Mark', 'Smits', 'Roger']
  age = [23, 45, 32]
  gender = ['male','male']
  </code></pre>
  
  <p>I want to write it to json files using the following template</p>
  
  <pre><code>{
    "resourceType" : "MyData",
    "name" : "{{human_name}}",
    "age" : "{{age}}",
    "gender":"{{gender}}"
  }
  </code></pre>
  
  <p>what i want is for the entries [Roger,32,(null)]</p>
  
  <p>my output json file should look like: </p>
  
  <pre><code>{
    "resourceType" : "MyData",
    "name" : "Roger",
    "age" : "32",
  }
  </code></pre>
  
  <p>Presently it looks like </p>
  
  <pre><code>{
    "resourceType" : "MyData",
    "name" : "Roger",
    "age" : "32",
    "gender":"",
  }
  </code></pre>
  
  <p>I tried using filters in jinja but not really working.</p>