keras/src/losses/losses.py/SparseCategoricalCrossentropy/__init__
class SparseCategoricalCrossentropy:    def __init__(
        self,
        from_logits=False,
        ignore_class=None,
        reduction="sum_over_batch_size",
        name="sparse_categorical_crossentropy",
        dtype=None,
    ):
        super().__init__(
            sparse_categorical_crossentropy,
            name=name,
            reduction=reduction,
            dtype=dtype,
            from_logits=from_logits,
            ignore_class=ignore_class,
        )
        self.from_logits = from_logits
        self.ignore_class = ignore_class