1. File "/local/lib/python2.7/site-packages/goocalendar/_calendar.py", line 622, in on_event_store_event_added
  2. self.update()
  4. File "/local/lib/python2.7/site-packages/goocalendar/_calendar.py", line 201, in update
  5. self.draw_events()
  7. File "/local/lib/python2.7/site-packages/goocalendar/_calendar.py", line 437, in draw_events
  8. max_y = self._selected_day.line_height
  10. 'NoneType' object has no attribute 'line_height'