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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 is_contradictory(self, other):
 """ Returns True if the two DictCells are unmergeable. """

        if not isinstance(other, DictCell):
            raise Exception("Incomparable")
        for key, val in self:
            if key in other.__dict__['p'] \
                    and val.is_contradictory(other.__dict__['p'][key]):
                return True
        return False