def METHOD_NAME(self, proxy_id, cls, object_id_tag, args):
    try:
        if '.' not in cls:
            self.logger.warning(
                'impossible to build rt proxy {}, wrongly formated class: {}'.format(proxy_id, cls)
            )
            return None
        module_path, name = cls.rsplit('.', 1)
        module = import_module(module_path)
        attr = getattr(module, name)
    except ImportError:
        self.logger.warning('impossible to build rt proxy {}, cannot find class: {}'.format(proxy_id, cls))
        return None
    try:
        return attr(id=proxy_id, object_id_tag=object_id_tag, instance=self.instance, **args)
    except TypeError as e:
        self.logger.warning('impossible to build rt proxy {}, wrong arguments: {}'.format(proxy_id, e))
        return None