def assign uploaded_file
      @dirty = true

      post_process(*only_process) if post_processing

      #[-29-]Reset the file size if the original file was reprocessed.
      instance_write(:file_size,   @queued_for_write[:original].size)
      instance_write(:fingerprint, @queued_for_write[:original].fingerprint) if instance_respond_to?(:fingerprint)
      updater = :"#{name}_file_name_will_change!"
      instance.send updater if instance.respond_to? updater
    end
def assign uploaded_file
      @dirty = true

      post_process(*only_process) if post_processing

      #[-29-]Reset the file size if the original file was reprocessed.
      instance_write(:file_size,   @queued_for_write[:original].size)
      instance_write(:fingerprint, @queued_for_write[:original].fingerprint) if instance_respond_to?(:fingerprint)
      updater = :"#{name}_file_name_will_change!"
      instance.send updater if instance.respond_to? updater
    end
[-15-]What gets called when you call instance.attachment = File. It clears
[-16-]errors, assigns attributes, and processes the file. It
[-17-]also queues up the previous file for deletion, to be flushed away on
[-18-]#save of its host.  In addition to form uploads, you can also assign
=begin
[-20-]another Paperclip attachment:
[-21-]  new_user.avatar = old_user.avatar
[-22-]  new_user.avatar = old_user.avatar
=end