Add a custom field to a Custom Taxonomy (WordPress)

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<?php 
/**
 * Used to attach a gallery shortcode to a custom taxonomy (but has more general uses)
 *
 * Uses code from: 
 * @link http://sabramedia.com/blog/how-to-add-custom-fields-to-custom-taxonomies
 */

// in functions.php / custom post setup file...

// A callback function to add a custom field to our "tf_foodmenu" taxonomy
function tf_menu_taxonomy_custom_fields($tag) {
   // Check for existing taxonomy meta for the term you're editing
    $t_id = $tag->term_id; // Get the ID of the term you're editing
    $term_meta = get_option( "taxonomy_term_$t_id" ); // Do the check
?>

<tr class="form-field">
    <th scope="row" valign="top">
        <label for="tax_gallery_code"><?php _e('Image Gallery Shortcode (optional)'); ?></label>
    </th>
    <td>
        <input type="text" name="term_meta[tax_gallery_code]" id="term_meta[tax_gallery_code]" size="25" style="width:60%;" value="<?php echo $term_meta['tax_gallery_code'] ? $term_meta['tax_gallery_code'] : ''; ?>"><br />
        <span class="description"><?php _e('Image Gallery Shortcode (optional)'); ?></span>
    </td>
</tr>

<?php
}

// A callback function to save our extra taxonomy field(s)
function save_taxonomy_custom_fields( $term_id ) {
    if ( isset( $_POST['term_meta'] ) ) {
        $t_id = $term_id;
        $term_meta = get_option( "taxonomy_term_$t_id" );
        $cat_keys = array_keys( $_POST['term_meta'] );
            foreach ( $cat_keys as $key ){
            if ( isset( $_POST['term_meta'][$key] ) ){
                $term_meta[$key] = $_POST['term_meta'][$key];
            }
        }
        //save the option array
        update_option( "taxonomy_term_$t_id", $term_meta );
    }
}

// Add the fields to the "presenters" taxonomy, using our callback function
add_action( 'tf_foodmenucat_edit_form_fields', 'tf_menu_taxonomy_custom_fields', 10, 2 );
// Save the changes made on the "presenters" taxonomy, using our callback function
add_action( 'edited_tf_foodmenucat', 'save_taxonomy_custom_fields', 10, 2 );

?>

<?php 
// -------------------------------------
// ** In Template **
//
// Grab & echo the output 
// (in this case it's a shortcode, so process it in the template)
// -------------------------------------

// Taxonomies can have a gallery shortcode for sidebar images
$taxCustomFields = get_option( "taxonomy_term_$term->term_id" );
$taxonomyGalleryShortCode = isset($taxCustomFields['tax_gallery_code']) ? $taxCustomFields['tax_gallery_code'] : false;
             ?>                 
<?php if( $taxonomyGalleryShortCode ): ?>
    <?php echo do_shortcode( $taxonomyGalleryShortCode); ?>
<?php endif; ?>