Get an array wich contains the post_name of every post that has the custom post_type “pelicula”

<?php // query for your post type
    $post_type_query  = new WP_Query(  
        array (  
            'post_type'      => 'pelicula',  
            'posts_per_page' => -1
        )  
    );   
    // we need the array of posts
    $posts_array      = $post_type_query->posts;   
    // create a list with needed information
    // the key equals the ID, the value is the post_title
    $post_title_array = wp_list_pluck( $posts_array, 'post_title', 'ID' );
    var_dump($post_title_array);
    ?>