def pre_tracer(self, obj, name, old, new, handler):
        tracer = self._get_tracer()
        tracer.pre_tracer(obj, name, old, new, handler)
Simple comparison function
dataset/ETHPy150Open enthought/traits/traits/util/event_tracer.py/MultiThreadChangeEventRecorder.pre_tracer--crossover with--dataset/ETHPy150Open dwighthubbard/hostlists/hostlists/hostlists.py/cmp_compat