[partition table] fetchall or fetchone function can not get the returning rows

Hello,

I have a problem concerning the partition table.
When I store a record into one of the partition and use "RETURNING table_id" or "RETURNING *",  
I expect the same result when calling fetchall or fetchone function as not using partition.
However, it simply returns nothing.

Since  the serial primary key of my partition table is the FK of some other tables, I need to get the
id after each insertion. 
My solution now is to select the max id from the parent table.
I am wondering if there is any other alternatives to solve this problem.

Thank you in advance!
Rachel