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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 with_defaults(self, obj):
 """ Given a dict of hyperparameter settings, return a dict containing those settings augmented by the defaults for any keys missing from the dict. """

        self.check_valid_keys(obj)
        obj = dict(obj)
        for (key, value) in self.defaults.items():
            if key not in obj:
                obj[key] = value
        return obj