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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 set_items(self, items):
 """expects a list of key, value to work with"""

        res = []
        max_value = max(sum((rec[1] for rec in items)), 1)
        for key, val in items:
            res.append((key, val, val * 1.0 / max_value))
        self._items = res