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functions.php

<?php 
add_action('add_attachment', 'rename_attachment');
function rename_attachment($post_ID){
    $file = get_attached_file($post_ID);
	$get_file_title = get_post($post_ID);
	if($get_file_title->post_parent){
		$post_santize_title = sanitize_title(get_the_title($get_file_title->post_parent));
		$path = pathinfo($file);

		$newfilename = $post_santize_title."-".$post_ID;
		$newfile = $path['dirname']."/".$newfilename.".".$path['extension'];

		rename($file, $newfile);    
		update_attached_file( $post_ID, $newfile );
		$my_post = array(
		  'ID'           => $post_ID,
		  'post_title'   => $newfilename,
		 );
		wp_update_post( $my_post );		
	}

}