To be correct in getting actual data who manualy triggered your dag:

with create_session() as session:
    results = session.query(Log).filter(
        Log.dag_id == "your_dag_id",
        Log.event == "trigger",
        Log.execution_date == "here should be execution date of dagrun"
    ).first()
print(results.owner)

If you want to use this code inside some PythonOperator function with context input, then solution will be:

with create_session() as session:
    results = session.query(Log).filter(
        Log.dag_id == context["dag_run"].dag_id,
        Log.event == "trigger",
        Log.execution_date == context["dag_run"].execution_date
    ).first()
if results:
    print(f'User who manualy started dagRun: {results.owner}')
else:
    print('No data from log')

When results will be None?

• When your dag was triggered from another dag by using TriggerDagRunOperator

p.s. now i am looking for how to fetch info about who and from what dag_id has triggered my dag.