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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 register(self, resource, event, trigger, **kwargs):
 """Called in trunk plugin's AFTER_INIT"""

        super(AristaTrunkDriver, self).register(resource, event,
                                                trigger, kwargs)
        registry.subscribe(self.subport_create,
                           resources.SUBPORTS, events.AFTER_CREATE)
        registry.subscribe(self.subport_delete,
                           resources.SUBPORTS, events.AFTER_DELETE)
        registry.subscribe(self.trunk_create,
                           resources.TRUNK, events.AFTER_CREATE)
        registry.subscribe(self.trunk_update,
                           resources.TRUNK, events.AFTER_UPDATE)
        registry.subscribe(self.trunk_delete,
                           resources.TRUNK, events.AFTER_DELETE)
        self.core_plugin = directory.get_plugin()
        LOG.debug("Arista trunk driver initialized.")