title: Selecting only one random key-value pair from a particular attribute in JSON schema
body: <p>How can I get a new JSON schema from the given JSON schema with only one key-value pair chosen randomly from the "properties" attribute. It should also have the "title" and "type" attributes.   </p>
  
  <pre><code>{ "title": "animals object",
    "type": "object",
    "properties": {
       'cat': 'meow',
       'dog': 'woof',
       'cow': 'moo',
       'sheep': 'baaah',
       'bird': 'tweet'
    }
  };
  </code></pre>