docs: def remove_all_events(self, calendar_id):
          '''Removes all events from a calendar. WARNING: Be very careful using this.'''
          # todo: incomplete
  
          now = datetime.now(tz=self.timezone) # timezone?
          start_time = datetime(year=now.year - 1, month=now.month, day=now.day, hour=now.hour, minute=now.minute, second=now.second, tzinfo=self.timezone)
          end_time = datetime(year=now.year + 1, month=now.month, day=now.day, hour=now.hour, minute=now.minute, second=now.second, tzinfo=self.timezone)
          start_time = start_time.isoformat()
          end_time = end_time.isoformat()
  
  
          #events = self.service.events().list(calendarId = self.configured_calendar_ids[calendar_id], showDeleted = False).execute()
          events = self.service.events().list(calendarId = self.configured_calendar_ids[calendar_id], timeMin = start_time, timeMax = end_time, showDeleted = False).execute()
  
          print(len(events['items']))
  
          for event in events['items']:
              dt = None
              nb = DeepNonStrictNestedBunch(event)
              #print(event)
              if (nb.summary or nb.description or '').find('presentation') != -1:
                  print(nb.id)
                  print(nb.summary or nb.description)
                  print(nb.start)