how to enable pgcrypto - Mailing list pgsql-bugs

From Ze Victor Harry
Subject how to enable pgcrypto
Date
Msg-id CAPR6t4nNNzZ6-KcCHFOdR=S1PLD9LsJp7EJUcX6Mp2t7qF8STQ@mail.gmail.com
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hello again I have a small problem here can someone tell me briefly how to do it? I am getting this error 

When i give ant fresh_install it gives error PostgreSQL 'pgcrypto' extension installed /up to date? False (not installed) Create extension pgcrypto.

I have tried to look up for solutions and they all say I have to run a command 
# Login to your "dspace" database as a superuser
psql --username=postgres dspace
# Enable the pgcrypto extension on this database
CREATE EXTENSION pgcrypto;
 but where I got confused is from where do i run these commands.is it from cmd? or in pgadmin sql? I need clearly articulated  steps

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