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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 jsonable(self, *args, **options):
 """ return a public version of this instance that can be jsonified Note that this does not return _id, _created, _updated, the reason why is because lots of times you have a different name for _id (like if it is a user object, then you might want to call it user_id instead of _id) and I didn't want to make assumptions note 2, I'm not crazy about the name, but I didn't like to_dict() and pretty much any time I need to convert the object to a dict is for json, I kind of like dictify() though, but I've already used this method in so many places """

        d = {}
        for field_name, field in self.schema.normal_fields.items():
            field_val = getattr(self, field_name, None)
            field_val = field.jsonable(self, field_val)
            if field_val is not None:
                d[field_name] = field_val

        return d