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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 h_function(self, x, xsquare):
 """Computes the h-function as defined in Paillier's paper page 12, 'Decryption using Chinese-remaindering'. """

        return invert(self.l_function(powmod(self.public_key.g, x - 1, xsquare),x), x)