def temp_file(part)
      file_name = filename?(part)
      File.expand_path(File.join(msg_tmp_dir(),File.basename(file_name)))
    end
def temp_file(part)
      file_name = filename?(part)
      File.expand_path(File.join(msg_tmp_dir(),File.basename(file_name)))
    end
Helper for process template method to name a temporary filepath based on
 information in the part.  This version attempts to honor the name of the
 media as labeled in the part header and creates a unique temporary
 directory for writing the file so filename collision does not occur.
 Consumers of this method expect the directory structure to the file
 exists, if the method is overridden it is mandatory that this behavior is
 retained.