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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 get_camera_extended_properties(self):
 """Return camera extended properties."""

        resource = 'cameras/{}'.format(self.device_id)
        resource_event = self.publish_and_get_event(resource)

        if resource_event is None:
            return None

        self._camera_extended_properties = resource_event.get('properties')
        return self._camera_extended_properties