How can I retrieve the slug for a custom post type via name?

I found an alternative solution: get_post_type_archive_link( $post_type );

Instead of providing a slug, it retrieves the archive url for a designated custom post type.

e.g.

<a href="https://wordpress.stackexchange.com/questions/124559/<?php echo get_post_type_archive_link("books' ); ?>">Movies Archive</a>

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)