How to render a html form from json using flask?

How can I render a html form from a json object using python flask.

My json object will be like

"file_name": {'username': 'Required', 'groupname': 'Required'}

after rendering the html should look like

<form>
 <label>username</label>
 <input type="text" name="username" />
 <label>groupname</label>
 <input type="text" name="groupname" />
 <input type=submit />
</form>