Mapping the get_hashed_value to the actual partition

I have a table with hashed partitions, and was trying to figure out how to figure out where my data is (for restoration from an exp).

If I do something like
select dbms_utility.get_hash_value(:my_value,0,:num_partitions) from dual;
I get a number in return, however there is no such thing as 'partition_id', or I couldn't find it. Oracle assigns fairly random #'s to partitions (although consecutive), but I recall renaming them. The only way I can see this work is thru trial and error. (e.g. restore partition one by one and see what they have in them, and see what get_hash_value returns).

Does anybody have a better method?

Thanx.

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oracle 8.1.7, solaris 7