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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 _aggregate_func(self, aggregate):
 """ Return a suitable aggregate score function. """

        funcs = {"sum": add, "min": min, "max": max}
        func_name = aggregate.lower() if aggregate else 'sum'
        try:
            return funcs[func_name]
        except KeyError:
            raise TypeError("Unsupported aggregate: {}".format(aggregate))