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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 _dom_class(self, obj1, obj2):
 """Return the dominating numeric class between the two :obj1: TODO :obj2: TODO :returns: TODO """

        if isinstance(obj1, Double) or isinstance(obj2, Double):
            return Double
        if isinstance(obj1, Float) or isinstance(obj2, Float):
            return Float