Present EXIF data of a photo

I want to make a page where I can present de EXIF data of a photo.
Therefore a tried to make a plugin according to the plugin recipe. https://learn.getgrav.org/17/cookbook/plugin-recipes.

I left the example.php unchanged.
I adjusted the ExampleTwigExtension.php. in particular the public function exampleFunction()

public function exampleFunction()
    {
        $image_file = 'test.jpeg'
        $exif = exif_read_data($image_file, 0, true);
        foreach ($exif as $key => $section) {
          foreach ($section as $name => $val) {
            echo "$key.$name: $val \n";
          }
        }
       return;
    }

In the pageheader I set:
process:
twig: true
In the page I use {{ example() }} to present the EXIF data. This is however the intention.

I am almost certain that the php code is incorrect. I don't know exactly which one should be. Can anyone help me?
Thank you.
Peter

Did you check what exif_read_data() returns? I'd bet it's false, because it can't find 'test.jpeg'. Also your PHP code should end up in Fatal syntax error, because $image_file = 'test.jpeg' is missing semicolon at the end.

Thanks for answering. Found the solution.
First the path to the file was indeed wrong. Second the name of the plugin and the names of the php and yaml file were different. Third I found an error in the example.php file which is presented in the learn environment (plugin-recipes).
Line 14: require_once(DIR . '/twig/ExampleTwigExtension.php’); should be: require_once(DIR . '/ExampleTwigExtension.php’);
Last I got all the information in one line. I tried something with \n. But this did not work. <br> worked however.