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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 get_tss(self):
 """ Total sum of squares around class means Returns sum of squares over all class means """

        tss = 0
        for class_def in self.classes:
            if len(class_def) > 0:
                yc = self.y[class_def]
                css = yc - yc.mean()
                css *= css
                tss += sum(css)
        return tss