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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 fehalf(self):
 """get the KL parcov scaling matrix attribute. Create the attribute if it has not yet been created Returns ------- fehalf : pyemu.Matrix """

        if self.__fehalf != None:
            return self.__fehalf
        self.log("fehalf")
        self.__fehalf = self.parcov.u * (self.parcov.s ** (0.5))
        self.log("fehalf")
        return self.__fehalf