SQLAlchemy #event.listens_for(Class, 'after_insert') for SQL Expression "INSERT INTO table(cols) VALUES (values)" - python-3.x

Question

In my application data will be flowing to postgres database from different system (from hive using scoop). I want to run some code automatically when it is inserted to one of the tables (I created it with sqlaLchemy ORM - I know that after_insert hook doesn't work for sqlAlchemy Core). And for my purpose I can't use postgres trigger.
This is kind of my data model:
from sqlalchemy.orm import declarative_base, Session
from sqlalchemy import Column, Integer, String, event, DDL
Base = declarative_base()
class MainClass(Base):
__tablename__ = 'first_table'
id = Column(Integer, primary_key=True)
name = Column(String, nullable=False)
#event.listens_for(MainClass, 'after_insert')
def after_insert(Mapper, connection, target):
connection.execute(DDL(f'''INSERT INTO second_table(name, value) VALUES ('OK!', '{target.name}')'''))
class SecondClass(Base):
__tablename__ = 'second_table'
id = Column(Integer, primary_key=True)
name = Column(String, nullable=False)
value = Column(String, nullable=False)
Base.metadata.create_all(engine, checkfirst=True)
What is not working:
engine.execute('''INSERT INTO first_table(name) VALUES ('test1')''')
What is working (but I can't use such insert in my case):
insert = MainClass(name='test2')
with Session(bind=engine) as session:
session.add(insert)
session.commit()
Documentations says:
method sqlalchemy.orm.MapperEvents.after_insert(mapper, connection, target)
Receive an object instance after an INSERT statement is emitted corresponding to that instance.
Example argument forms:
from sqlalchemy import event
#event.listens_for(SomeClass, 'after_insert')
def receive_after_insert(mapper, connection, target):
"listen for the 'after_insert' event"
This event is used to modify in-Python-only state on the instance after an INSERT occurs, as well as to emit additional SQL statements on the given connection.
The event is often called for a batch of objects of the same class after their INSERT statements have been emitted at once in a previous step. In the extremely rare case that this is not desirable, the mapper() can be configured with batch=False, which will cause batches of instances to be broken up into individual (and more poorly performing) event->persist->event steps.
If this is something that sqlAlchemy ORM events doesn't support. Can you recommend me some workaround?