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Login as admin and access the realms tool and delete the the realm entitled '!su.can_su_realm'
Select the tool page that contains the SU Tool
Type the name of any non-admin or admin user and select 'Become User' button (the later case will fail the su but achieve results for this test)
I necessary, log our and re-login as an admin user
Return to realms tool and search for the above realm name
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