'Test to ensure that update is passed a value to update to'

def test_update_update_has_a_value(self):

    self.Person.drop_collection()
    author = self.Person.objects.create(name='Test    User')
    with self.assertRaises(OperationError):
        self.Person.objects(pk=author.pk).update({})
    with self.assertRaises(OperationError):
        self.Person.objects(pk=author.pk).update_one({})
