I have a form with `id` equal to `webform_client_form_3`.  I have a particular field that I'm altering by applying a class to it like so:

    $form['submitted']['estimated_annual_distribution_of_effort']['sensor_technology']['#attributes']['class'][] = 'span1';

This all works great.  However, I also need to add a class on to the label for that particular element as well.  Looking through the `$form` array, I haven't been able to find anything that gives access to the labels.  Am I just missing something or are the labels not part of the `$form` array?