def _update_num_annotations(self, target_bboxes: np.ndarray):
    '\n        :param target_bboxes: (N, 5(xmin, ymin, xmax, ymax, class))\n        '
    counts = list(map((lambda i: np.count_nonzero((target_bboxes[:, 4] == i))), range(self._n_classes)))
    self.num_annotations_by_classes = list(map((lambda i: (counts[i] + self.num_annotations_by_classes[i])), range(self._n_classes)))
:param target_bboxes: (N, 5(xmin, ymin, xmax, ymax, class))
def _update_num_annotations(self, target_bboxes: np.ndarray):
    '\n        \n        '
    counts = list(map((lambda i: np.count_nonzero((target_bboxes[:, 4] == i))), range(self._n_classes)))
    self.num_annotations_by_classes = list(map((lambda i: (counts[i] + self.num_annotations_by_classes[i])), range(self._n_classes)))