Copyright

17class Copyright18{19    /**20     * Copyright URL21     *22     * @var ?string23     * @see get_url()24     */25    public $url;26 27    /**28     * Attribution29     *30     * @var ?string31     * @see get_attribution()32     */33    public $label;34 35    /**36     * Constructor, used to input the data37     *38     * For documentation on all the parameters, see the corresponding39     * properties and their accessors40     */41    public function __construct(42        ?string $url = null,43        ?string $label = null44    ) {45        $this->url = $url;46        $this->label = $label;47    }48 49    /**50     * String-ified version51     *52     * @return string53     */54    public function __toString()55    {56        // There is no $this->data here57        return md5(serialize($this));58    }59 60    /**61     * Get the copyright URL62     *63     * @return string|null URL to copyright information64     */65    public function get_url()66    {67        if ($this->url !== null) {68            return $this->url;69        }70 71        return null;72    }73 74    /**75     * Get the attribution text76     *77     * @return string|null78     */79    public function get_attribution()80    {81        if ($this->label !== null) {82            return $this->label;83        }84 85        return null;86    }87}