def __init__(self, normalize: bool = True):
        """
        :param normalize: whether to normalize the input with
            2-norm = 1 before computing the distance.
        """
        super().__init__()
        # vectorized version of class means
        self.register_buffer("class_means", None)
        self.class_means_dict = {}

        self.normalize = normalize
        self.max_class = -1

        :param normalize: whether to normalize the input with
            2-norm = 1 before computing the distance.
        
avalanche/models/ncm_classifier.py