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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 split_six(series=None):
 """ Given a Pandas Series, get a domain of values from zero to the 90% quantile rounded to the nearest order-of-magnitude integer. For example, 2100 is rounded to 2000, 2790 to 3000. Parameters series: Pandas series, default None Returns ------- list """

    if pd is None:
        raise ImportError('The Pandas package is required'
                          ' for this functionality')
    if np is None:
        raise ImportError('The NumPy package is required'
                          ' for this functionality')

    def base(x):
        if x > 0:
            base = pow(10, math.floor(math.log10(x)))
            return round(x/base)*base
        else:
            return 0

    quants = [0, 50, 75, 85, 90]
    # Some weirdness in series quantiles a la 0.13.
    arr = series.values
    return [base(np.percentile(arr, x)) for x in quants]