In the Form API documentation for the 'item' element (http://api.drupal.org/api/drupal/developer!topics!forms_api_reference.html/7#item), a link is provided as a usage example. However, this link points to contact.module, whereas the function where the 'item' element is used now resides in contact.pages.inc.
I recommend changing the 'usage example' link (found at the above URL) from http://api.drupal.org/api/drupal/modules!contact!contact.module/7 to http://api.drupal.org/api/drupal/modules!contact!contact.pages.inc/7.
Closed: won't fix
API documentation files
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Thanks for working to improve Drupal.
This is for the Drupal 7 Form API reference. Since Drupal 7 is past end-of-life this is now a "won't fix".
Work on documentation for form elements for supported versions of Drupal is at 📌 [meta] Move/Create Form Element Documentation Active and 🌱 [Meta] Improve documentation for Render and Form Elements Active .