How to setup role to add addition account to the managed system - e.g. testing account in addition to my normal account

We will create another account (for the same system) by creating another link to the same system in the role. Next, we need to overload the attribute that defines a unique account identifier (has checked 'Is identifier'). In this overloaded attribute, we modify the transformation into the system so that the identifier differs from the default system (for example: "return attributeValue +'test;").