def identity_key_from_instance(self, instance):
        return self.identity_key_from_primary_key(
            self.primary_key_from_instance(instance))
Return the identity key for the given instance, based on
dataset/ETHPy150Open goFrendiAsgard/kokoropy/kokoropy/packages/sqlalchemy/orm/mapper.py/Mapper.identity_key_from_instance