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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 priorfactors(self):
 """Combinartion of priorfactors from all populations """

        priorfactors = {}
        for pop in self.poplist:
            for f in pop.priorfactors:
                if f in priorfactors:
                    if pop.priorfactors[f] != priorfactors[f]:
                        raise ValueError('prior factor %s is inconsistent!' % f)
                else:
                    priorfactors[f] = pop.priorfactors[f]
        return priorfactors