I'm trying to create a dictionary managed tablespace

" create tablespace data01
datafile "c:\......." size 2m
extent management dictionary"

I get ora-12913 error
error in the documentation says

"ORA-12913 Cannot create dictionary managed tablespace

Cause: An attempt was made to create a dictionary managed tablespace in a database whose SYSTEM tablespace is locally managed.

Action: Create a locally managed tablespace."

Could someone explain this and tell me what to do