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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 json_dumps(cls, obj, **kwargs):
 """ A rewrap of json.dumps done for one reason - to inject a custom `cls` kwarg :param obj: :param kwargs: :return: :rtype: str """

        if 'cls' not in kwargs:
            kwargs['cls'] = cls.json_encoder
        return json.dumps(obj, **kwargs)