_event_class_cls = property(lambda s: bt2_event_class._EventClass)
_trace_class_cls = property(lambda s: bt2_trace_class._TraceClass)
_clock_class_cls = property(lambda s: bt2_clock_class._ClockClass)
_event_class_cls = property(lambda s: bt2_event_class._EventClass)
_trace_class_cls = property(lambda s: bt2_trace_class._TraceClass)
_clock_class_cls = property(lambda s: bt2_clock_class._ClockClass)