title: Get the first value from a nested object
body: <p>I have an object called <code>allInvalidFields</code> which lists invalid fields under an identifier e.g <code>_0</code> or <code>_3</code></p>
  
  <p>The object could look like this</p>
  
  <pre><code>allInvalidFields = {
      "_0" : {
          0: input.foo,
          1: select.la
      }
      "_1" : {
          0: input.foofoo,
          1: select.lala
      }
  }
  </code></pre>
  
  <p>But equally it could not have <code>_0</code> as the first key and could look like this:</p>
  
  <pre><code>allInvalidFields = {
      "_1" : {
          0: input.alice,
          1: select.bob
      }
      "_3" : {
          0: input.foo
      }
  }
  </code></pre>
  
  <p>How can I get the <strong>first</strong> value from the <strong>first</strong> object in the list? So in the example above it would be <code>input.foo</code> or <code>input.alice</code> depending on which dataset was being searched.</p>