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Authentication Init Object is created.
it runs the apicheck function if function if this says they are compatible then it will run the init function, after this it will run the register_callback_routines function. The data from this function is then parsed onto the register_callback function
Authentication
The do_authentication function is function is called, this is the start of the authentication routine/procedure.
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This is the first set of callbacks run and takes a Authentication a Authentication preauth object
Auth
The auth callbacks are then called with a Authentication auth object
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