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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 t_measures(dirname, time_func, measure_func):
 """Calculate a measure over time for a single output directory, and its uncertainty. Parameters dirname: str Path to a model output directory. time_func: function Function which takes a :class:`Model` instance as a single argument, and returns its time. measure_func: function Function which takes a :class:`Model` instance as a single argument, and returns the measure of interest, and its uncertainty. Returns ------- ts: np.ndarray Times. measures: np.ndarray Measures. measure_errs: np.ndarray Measure uncertainties. """

    ts, measures, measure_errs = [], [], []
    for fname in get_filenames(dirname):
        m = filename_to_model(fname)
        ts.append(time_func(m))
        meas, meas_err = measure_func(m)
        measures.append(meas)
        measure_errs.append(meas_err)
    return np.array(ts), np.array(measures), np.array(measure_errs)