keras/src/backend/numpy/trainer.py/NumpyTrainer/predict_step
class NumpyTrainer:    def predict_step(self, data):
        x, _, _ = data_adapter_utils.unpack_x_y_sample_weight(data)
        if self._call_has_training_arg:
            y_pred = self(x, training=False)
        else:
            y_pred = self(x)
        return y_pred