Get attribute for Beautifulsoup object
        :param soup: Beautifulsoup object
        :param key: attribute key
        :param data_type: Data type(int, float, etc...)
        :param unknown: attribute key not exists value(default:None)
        :return: (data_type)attribute value

def get_attribute_stats(cls, soup, key, data_type=str, unknown=None):
        """
        Get attribute for Beautifulsoup object
        :param soup: Beautifulsoup object
        :param key: attribute key
        :param data_type: Data type(int, float, etc...)
        :param unknown: attribute key not exists value(default:None)
        :return: (data_type)attribute value
        """
        value = cls.get_attribute(soup, key, unknown)

        if value and value != unknown:
            return data_type(value)
        return unknown