post_tags_meta_box() WordPress Function

function post_tags_meta_box( $post, $box ) {
	$defaults = array( 'taxonomy' => 'post_tag' );
	if ( ! isset( $box['args'] ) || ! is_array( $box['args'] ) ) {
		$args = array();
	} else {
		$args = $box['args'];
	}
	$parsed_args           = wp_parse_args( $args, $defaults );
	$tax_name              = esc_attr( $parsed_args['taxonomy'] );
	$taxonomy              = get_taxonomy( $parsed_args['taxonomy'] );
	$user_can_assign_terms = current_user_can( $taxonomy->cap->assign_terms );
	$comma                 = _x( ',', 'tag delimiter' );
	$terms_to_edit         = get_terms_to_edit( $post->ID, $tax_name );
	if ( ! is_string( $terms_to_edit ) ) {
		$terms_to_edit = '';
	}
	?>
<div class="tagsdiv" id="<?php echo $tax_name; ?>">
	<div class="jaxtag">
	<div class="nojs-tags hide-if-js">
		<label for="tax-input-<?php echo $tax_name; ?>"><?php echo $taxonomy->labels->add_or_remove_items; ?></label>
		<p><textarea name="<?php echo "tax_input[$tax_name]"; ?>" rows="3" cols="20" class="the-tags" id="tax-input-<?php echo $tax_name; ?>" <?php disabled( ! $user_can_assign_terms ); ?> aria-describedby="new-tag-<?php echo $tax_name; ?>-desc"><?php echo str_replace( ',', $comma . ' ', $terms_to_edit ); // textarea_escaped by esc_attr() ?></textarea></p>
	</div>
	<?php if ( $user_can_assign_terms ) : ?>
	<div class="ajaxtag hide-if-no-js">
		<label class="screen-reader-text" for="new-tag-<?php echo $tax_name; ?>"><?php echo $taxonomy->labels->add_new_item; ?></label>
		<input data-wp-taxonomy="<?php echo $tax_name; ?>" type="text" id="new-tag-<?php echo $tax_name; ?>" name="newtag[<?php echo $tax_name; ?>]" class="newtag form-input-tip" size="16" autocomplete="off" aria-describedby="new-tag-<?php echo $tax_name; ?>-desc" value="" />
		<input type="button" class="button tagadd" value="<?php esc_attr_e( 'Add' ); ?>" />
	</div>
	<p class="howto" id="new-tag-<?php echo $tax_name; ?>-desc"><?php echo $taxonomy->labels->separate_items_with_commas; ?></p>
	<?php elseif ( empty( $terms_to_edit ) ) : ?>
		<p><?php echo $taxonomy->labels->no_terms; ?></p>
	<?php endif; ?>
	</div>
	<ul class="tagchecklist" role="list"></ul>
</div>
	<?php if ( $user_can_assign_terms ) : ?>
<p class="hide-if-no-js"><button type="button" class="button-link tagcloud-link" id="link-<?php echo $tax_name; ?>" aria-expanded="false"><?php echo $taxonomy->labels->choose_from_most_used; ?></button></p>
<?php endif; ?>
	<?php
}