请求帮助修复php脚本错误

i got this unexpected error after site builder set up. Since I'm not familiar with CSS or PHP scripts, I'm not able to see the error which should be on line 8 and line 19 (according to the 500 error code).

There was no closing line (?>) at the end of the script, which is now added by me. Can you plese help me to fix other errors? thank you in advance for your help

<?php
/**
 * @see       https://github.com/zendframework/zend-diactoros for the canonical source repository
 * @copyright Copyright (c) 2018 Zend Technologies USA Inc. (https://www.zend.com)
 * @license   https://github.com/zendframework/zend-diactoros/blob/master/LICENSE.md New BSD License
 */

declare(strict_types=1); // Error highlighted issue with this line.

namespace Zend\Diactoros;

/**
 * Create an uploaded file instance from an array of values.
 *
 * @param array $spec A single $_FILES entry.
 * @throws Exception\InvalidArgumentException if one or more of the tmp_name,
 *     size, or error keys are missing from $spec.
 */
function createUploadedFile(array $spec) : UploadedFile // Error highlighted issue with this line.
{
    if (! isset($spec['tmp_name'])
        || ! isset($spec['size'])
        || ! isset($spec['error'])
    ) {
        throw new Exception\InvalidArgumentException(sprintf(
            '$spec provided to %s MUST contain each of the keys "tmp_name",'
            . ' "size", and "error"; one or more were missing',
            __FUNCTION__
        ));
    }

    return new UploadedFile(
        $spec['tmp_name'],
        $spec['size'],
        $spec['error'],
        isset($spec['name']) ? $spec['name'] : null,
        isset($spec['type']) ? $spec['type'] : null
    );
}
?>

Given the errors are about the only lines that consist of php7+ only code, the problem is likely an outdated version of php.

There are two solutions: the better solution is to upgrade your php version to 7.2; ask your hosting provider if they're able to accommodate you in that regard.

Your other option is probably faster: simply remove the php7 code. The problem is about these parts:

declare(strict_types=1);

And

(...) : UploadedFile

Both of these can be removed without consequence.

In short: Remove line 8, and replace line 19 with:

function createUploadedFile(array $spec)

Edit:

To do it really well, you might consider adding this:

 * @return UploadedFile

Right between the lines with @param and @throws. It's the php5.x alternative for : UploadedFile.

PS: The ?> thing is supposed to be missing. Having it still works in most cases, but taking it out again is the better way.