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    // Write the new file to the local filesystem.

      // Don't try to write it if it uses a stream wrapper that isn't writeable

      // (for example, if it is a remotely-hosted video).

      $scheme = file_uri_scheme($entity->uri);

      $wrappers = file_get_stream_wrappers(STREAM_WRAPPERS_WRITE);

      if (empty($wrappers[$scheme])) {

        return;

      }

      // Check for an existing file with the same URI.

      $existing_files = file_load_multiple(array(), array('uri' => $entity->uri));

      $existing = (object) array('uri' => NULL, 'uuid' => NULL);

      if (count($existing_files)) {

        $existing = reset($existing_files);

      }

      // If this is a new file and there is an existing file with the same URI,

      // but a different uuid then rename this file.

      if ($entity->is_new && $entity->uri == $existing->uri && $entity->uuid != $existing->uuid) {

        $uri = $entity->uri;

        $replace = FILE_EXISTS_RENAME;

      }

      // If this has an id, meaning UUID has already matched the uuid to an

      // existing file, but it has a URI that matches a file with a different

      // uuid, then load the file with the matching uuid and use the URI from

      // that file. The existing file with the matching uuid is most likely a

      // file that was previously renamed, e.g. as in the condition above, to

      // avoid conflict. The uuid matches because they are the same file, but

      // the URI does not because an incrementing number was added as part of

      // the renaming.

      elseif ($entity->uri == $existing->uri && $entity->uuid != $existing->uuid) {

        $file = file_load($entity->fid);

        $uri = $file->uri;

        $replace = FILE_EXISTS_REPLACE;

      }

      // Otherwise create a new file or replace the existing file contents.

      else {

        $uri = $entity->uri;

        $replace = FILE_EXISTS_REPLACE;

      }

      $directory = drupal_dirname($uri);

      $entity->uri = file_unmanaged_save_data(base64_decode($entity->file_contents), $uri, $replace);

 * Implementations hook_uuid_entities_features_export_entity_alter().