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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def instance_signals_and_handlers(cls, instance):
 """Calculate per-instance signals and handlers."""

        isignals = cls._signals.copy()

        ihandlers = cls._build_instance_handler_mapping(
            instance,
             cls._signal_handlers
        )
        return isignals, ihandlers