def add_short_description(self, description):
        deprecated(description)
        self.short_descriptions.add(description)
ExtRegistry.register: adds a new key.
dataset/ETHPy150Open STIXProject/python-stix/stix/core/stix_header.py/STIXHeader.add_short_description--crossover with--dataset/ETHPy150Open xtrementl/focus/tests/unit/test_registry.py/TestExtRegistry.testNewKey__register