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This may be useful in situations where the client application uses a single account to access USAS, but still wishes to use USAS security features to limit what accounts can be seen or functions performed.
When posting requisitions, the username used in the impersonation call will also be used as the "requisitioner" in USAS. This is currently true only for requisitions and not for any other data types.
Mapping Foreign Users to USAS Profiles by Convention
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