Cisco ASA Dynamic NAT with DMZ

I was following the Cisco ASA Dynamic NAT with DMZ, however a bit confused in regard to:

ASA1(config)# object network PUBLIC_POOL -> What does it refer, shouldn’t be the public IP address on ASA (
ASA1(config-network-object)# range

I have tried to implement similar, however i have the following error:

[ok] object network dmz
    object network dmz
[ok] host
[ERROR] nat stactic outside net-to-net
            Address overlaps with outside interface address.
ERROR: NAT Policy is not downloaded