code: def _update_ipython_widget(self, value=None):
          
  
          # Create and display an empty progress bar widget,
          # if none exists.
          if not hasattr(self, '_widget'):
              self._widget = create_progress_widget()
              if in_ipython_frontend() and is_widgets_available():
                  display(self._widget)
              self._widget.value = 0
  
          # Calculate percent completion, and update progress bar
          percent = (float(value)/self._total) * 100.0
          self._widget.value = percent
          self._widget.description =' ({0:>6s}%)'.format('{0:.2f}'.format(percent))
docs: Update the progress bar to the given value (out of a total
          given to the constructor).
  
          This method is for use in the IPython notebook 2+.