text: from datetime import datetime
  
  from django.db.models import Value
  from django.db.models.fields import DateTimeField
  from django.db.models.lookups import YearComparisonLookup
  from django.test import SimpleTestCase
  
  
  class YearComparisonLookupTests(SimpleTestCase):
      def test_get_bound(self):
          look_up = YearComparisonLookup(
              lhs=Value(datetime(2010, 1, 1, 0, 0, 0), output_field=DateTimeField()),
              rhs=Value(datetime(2010, 1, 1, 23, 59, 59), output_field=DateTimeField()),
          )
          msg = 'subclasses of YearComparisonLookup must provide a get_bound() method'
          with self.assertRaisesMessage(NotImplementedError, msg):
              look_up.get_bound(datetime(2010, 1, 1, 0, 0, 0), datetime(2010, 1, 1, 23, 59, 59))
  