def update(self, n: int | float = 1):
        """
        Increases latest iterable with specified number of steps.
        Parameters:
            n: number of steps completed.
        """
        callback = self._progress_callback()
        if callback and len(self.iterables) > 0:
            current_iterable = self.iterables[-1]
            if current_iterable.index is None:
                raise IndexError("Index not set.")
            current_iterable.index += n
            callback(self.iterables)
        else:
            return

        Increases latest iterable with specified number of steps.
        Parameters:
            n: number of steps completed.
        
gradio/helpers.py