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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 _replace_fields(self, json_dict):
 """ Delete this object's attributes, and replace with those in json_dict. """

        for key in self._json_dict.keys():
            if not key.startswith("_"):
                delattr(self, key)
        self._json_dict = json_dict
        self._set_fields(json_dict)