<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def td_taper(out, start, end, beta=8, side='left'):
 """Applies a taper to the given TimeSeries. A half-kaiser window is used for the roll-off. Parameters out : TimeSeries The ``TimeSeries`` to taper. start : float The time (in s) to start the taper window. end : float The time (in s) to end the taper window. beta : int, optional The beta parameter to use for the Kaiser window. See ``scipy.signal.kaiser`` for details. Default is 8. side : {'left', 'right'} The side to apply the taper to. If ``'left'`` (``'right'``), the taper will roll up (down) between ``start`` and ``end``, with all values before ``start`` (after ``end``) set to zero. Default is ``'left'``. Returns ------- TimeSeries The tapered time series. """

    out = out.copy()
    width = end - start
    winlen = 2 * int(width / out.delta_t)
    window = Array(signal.get_window(('kaiser', beta), winlen))
    xmin = int((start - out.start_time) / out.delta_t)
    xmax = xmin + winlen//2
    if side == 'left':
        out[xmin:xmax] *= window[:winlen//2]
        if xmin > 0:
            out[:xmin].clear()
    elif side == 'right':
        out[xmin:xmax] *= window[winlen//2:]
        if xmax < len(out):
            out[xmax:].clear()
    else:
        raise ValueError("unrecognized side argument {}".format(side))
    return out