How to Automatically Add Default Image Links

I would like to automatically links the image to the media file. I had it before but lost after some uprgades.
I was looking on web but i only found solutions to remove automatically links. However it requires to add code in theme fuctions php. Like that:

function wpb_imagelink_setup() {
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$image_set = get_option( ‘image_default_link_type’ );
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if ($image_set !== ‘none’) {
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update_option(‘image_default_link_type’, ‘none’);
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}
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}
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add_action(‘admin_init’, ‘wpb_imagelink_setup’, 10);

Any suggestions how to change code to add atomatically links?