Drupal 8 - Extract file url from media field

file.php

<?php
$url = $item['content']['field_media_image'][0]['#url'];
$media_id = $url->getRouteParameters()['media'];
$media = entity_load('media', $media_id);
$filefield = $media->field_image_file->referencedEntities();
$entity = current($entity);
$uri = $entity->getFileUri();
$url = Url::fromUri(file_create_url($uri))->toString();