How can I clone a twins DataBase.

I need to have a clone copy of an existing Oracle Db, this twin Db = should
run in a second Oracle instance.
The twin copy of the db should be different only for DB_NAME and for = files
location (datafiles, log files, control files etc.). At any time I should be able to copy original datafiles over the twin Db datafiles.

This is because I'm going to have comparative tests and I need to = restore initial conditions after each test execution.

Thanks!

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