@abc.abstractmethod
    def _directivity(self, theta, phi):
        pass
Collect information about whether each token type occurs
dataset/ETHPy150Open python-acoustics/python-acoustics/acoustics/directivity.py/Directivity._directivity--crossover with--dataset/ETHPy150Open nltk/nltk/nltk/tokenize/punkt.py/PunktTrainer._get_orthography_data