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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 diffse(self, x1, x2):
 """Standard error of the difference between the function values at x1 and x2"""
 
        f1, f1se = self(x1)
        f2, f2se = self(x2)
        if self.paired:
            fx1 = np.array(self.cache[tuple(x1)])
            fx2 = np.array(self.cache[tuple(x2)])
            diffse = np.std(fx1-fx2, ddof=1)/self.N**.5 
            return diffse
        else:
            return (f1se**2 + f2se**2)**.5