n-value">
      <label>Social security number</label>
      <ssn-input class="paper-input-input"></ssn-input>
    </paper-input-container>


If you're using a `<paper-input-container>` imperatively, it's important to make sure
that you attach its children (the `iron-input` and the optional `label`) before you
attach the `<paper-input-container>` itself, so that it can be set up correctly.

### Validation

If the `auto-validate` attribute is set, the input container will validate the input and update
the con