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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def plot_time_series(sdat, lovs):
 """Plot requested time series. Args: sdat (:class:`~stagpy.stagyydata.StagyyData`):
 a StagyyData instance. lovs (nested list of str):
 nested list of series names such as the one produced by :func:`stagpy.misc.list_of_vars`. Other Parameters: conf.time.tstart: the starting time. conf.time.tend: the ending time. """

    sovs = misc.set_of_vars(lovs)
    tseries = {}
    times = {}
    metas = {}
    for tvar in sovs:
        series, time, meta = get_time_series(
            sdat, tvar, conf.time.tstart, conf.time.tend)
        tseries[tvar] = series
        metas[tvar] = meta
        if time is not None:
            times[tvar] = time
    tseries['t'] = get_time_series(
        sdat, 't', conf.time.tstart, conf.time.tend)[0]

    _plot_time_list(sdat, lovs, tseries, metas, times)