code: def test_reject_alias_that_already_exists(self):
      with self.assertRaises(CalendarNameCollision):
          self.dispatcher.register_calendar_alias("ICE", "NOT_ICE")
  
      with self.assertRaises(CalendarNameCollision):
          self.dispatcher.register_calendar_alias(
              "ICE_ALIAS", "NOT_ICE"
          )
  
file_path: catalyst/tests/calendars/test_calendar_dispatcher.py
imports: from catalyst.errors import CalendarNameCollision, CyclicCalendarAlias, InvalidCalendarName
  from catalyst.testing import CatalystTestCase
  from catalyst.utils.calendars.calendar_utils import TradingCalendarDispatcher
  from catalyst.utils.calendars.exchange_calendar_ice import ICEExchangeCalendar
label_desc: Use image node_id 6 for calling the CalendarAliasTestCase obj's underlying member method code with example usage: obj.test_reject_alias_that_already_exists() without return types