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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 finalize(self, errs):
 """Update target collection with calculated maximum values. """

        for group, value in self._groups.items():
            doc = {'group': group, 'value': value}
            self._target_coll.update({'group': group}, doc, upsert=True)
        return True