anything to JSON in python

gistfile1.py

def jsonize(self, data_dict):
        dict_string = {}
        for key, value in data_dict.items():
            if isinstance(value, QuerySet):
                dict_string[key] = serializers.serialize('json', value)
            else:
                dict_string[key] = json.dumps(value)
        json_str = '{'
        for key, value in dict_string.items():
            json_str += '"%s":%s,' % (key, value)
        json_str = json_str[:-1] + '}'
        return json_str