keras/src/utils/file_utils.py/DLProgbar/__call__
class DLProgbar:            def __call__(self, block_num, block_size, total_size):
                if total_size == -1:
                    total_size = None
                if not self.progbar:
                    self.progbar = Progbar(total_size)
                current = block_num * block_size

                if total_size is None:
                    self.progbar.update(current)
                else:
                    if current < total_size:
                        self.progbar.update(current)
                    elif not self.finished:
                        self.progbar.update(self.progbar.target)
                        self.finished = True