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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 omitted_jco(self):
 """get the omitted jco Returns ------- omitted_jco : pyemu.Jco Note ---- returns a reference if ErrorVariance.__omitted_jco is None, then dynamically load the attribute before returning """

        if self.__omitted_jco is None:
            self.log("loading omitted_jco")
            self.__load_omitted_jco()
            self.log("loading omitted_jco")
        return self.__omitted_jco