Edit: session.php

<?php /** * Session API * * @since 4.0.0 * @deprecated 4.7.0 */ _deprecated_file( basename( __FILE__ ), '4.7.0' ); require_once ABSPATH . WPINC . '/class-wp-session-tokens.php'; require_once ABSPATH . WPINC . '/class-wp-user-meta-session-tokens.php';

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