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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 quantiles(self, bins, mask=NotSpecified):
 """ Construct a Classifier computing quantiles of the output of ``self``. Every non-NaN data point the output is labelled with an integer value from 0 to (bins - 1). NaNs are labelled with -1. If ``mask`` is supplied, ignore data points in locations for which ``mask`` produces False, and emit a label of -1 at those locations. Parameters bins : int Number of bins labels to compute. mask : zipline.pipeline.Filter, optional Mask of values to ignore when computing quantiles. Returns ------- quantiles : zipline.pipeline.classifiers.Quantiles A Classifier producing integer labels ranging from 0 to (bins - 1). """

        if mask is NotSpecified:
            mask = self.mask
        return Quantiles(inputs=(self,), bins=bins, mask=mask)