WP_Application_Passwords::chunk_password( string $raw_password )

Source

File: wp-includes/class-wp-application-passwords.php

public static function chunk_password( $raw_password ) {
		$raw_password = preg_replace( '/[^a-z\d]/i', '', $raw_password );

		return trim( chunk_split( $raw_password, 4, ' ' ) );
	}