    # File lib/fog/google/models/storage/file.rb, line 48
            def copy(target_directory_key, target_file_key)
              requires :directory, :key
              service.copy_object(directory.key, key, target_directory_key, target_file_key)
              target_directory = service.directories.new(:key => target_directory_key)
              target_directory.files.get(target_file_key)
            end