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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 H10(self):
        "Difference variance."
        c = (self.rlevels * self.p_xminusy).sum(1)
        c1 = np.tile(c, (self.nlevels,1)).transpose()
        e = self.rlevels - c1
        return (self.p_xminusy * e ** 2).sum(1)