environment (allowing for window resizes) [default: False].
    smoothing  : float, optional
        Exponential moving average smoothing factor for speed estimates
        (ignored in GUI mode). Ranges from 0 (average speed) to 1
        (current/instantaneous speed) [default: 0.3].
    bar_format  : str, optional
        Specify a custom bar string formatting. May impact performance.
        [default: '{l_bar}{bar}{r_bar}'], where
        l_bar='{desc}: {percentage:3.0f}%|' and
        r_bar='| {n_fmt}/{total_fmt} [{elapsed}<{remaining}, '
            '{rate_fmt}{postfix}]'
        Possible vars: l_bar, bar, r_bar, n, n_fmt, total, total_fmt,
            percentage, elapsed, elapsed_s, ncols, nrows, desc, unit,
            rate, rate_fmt, rate_noinv, rate_noinv_fmt,
            rate_inv, rate_inv_fmt, postfix, unit_divisor,
            remaining, remaining_s, eta.
        Note that a trailing ": " is automatically removed after {desc}
        if the latter is empty.
    initial  : int or float, optional
        The initial counter value. Useful when restarting a progress
        bar [default: 0]. If using float, consider specifying `{n:.3f}`
        or similar in `bar_format`, or specifying `unit_scale`.
    position  : int, optional
        Specify the line offset to print this bar (starting from 0)
        Automatic if unspecified.
        Useful to manage multiple bars at once (eg, from threads).
    postfix  : dict or *, optional
        Specify additional stats to display at the end of the bar.
        Calls `set_postfix(**postfix)` if possible (dict).
    unit_divisor  : float, optional
        [default: 1000], ignored unless `unit_scale` is True.
    write_bytes  : bool, optional
        Whether to write bytes. If (default: False) will write unicode.
    lock_args  : tuple, optional
        Passed to `refresh` for intermediate output
        (initialisation, iterating, and updating).
    nrows  : int, optional
        The screen height. If specified, hides nested bars outside this
        bound. If unspecified, attempts to use environment height.
        The fallback is 20.
    colour  : str, optional
        Bar colour (e.g. 'green', '#00ff00').
    delay  : float, optional
        Don't display until [default: 0] seconds have elapsed.
    gui  : bool, optional
        WARNING: internal parameter - do not use.
        Use tqdm.gui.tqdm(...) instead. If set, will attempt to use
        matplotlib animations for a graphical output [default: False].

    Returns
    -------
    out  : decorated iterator.
    rb