def _import_next_layer(self, proto, length):
if self._exproto == '<STR_LIT:null>' and self._exlayer == '<STR_LIT:None>':<EOL><INDENT>from pcapkit.protocols.raw import Raw as NextLayer<EOL><DEDENT>else:<EOL><INDENT>from pcapkit.foundation.analysis import analyse as NextLayer<EOL><DEDENT>if length == <NUM_LIT:0>:<EOL><INDENT>next_ = NoPayload()<EOL><DEDENT>elif self._onerror:<EOL><INDENT>next_ = beholder_ng(NextLayer)(self._file, length, _termination=self._sigterm)<EOL><DEDENT>else:<EOL><INDENT>next_ = NextLayer(self._file, length, _termination=self._sigterm)<EOL><DEDENT>return next_<EOL>
Import next layer extractor.

        Positional arguments:
            * proto -- str, next layer protocol name
            * length -- int, valid (not padding) length

        Returns:
            * bool -- flag if extraction of next layer succeeded
            * Info -- info of next layer
            * ProtoChain -- protocol chain of next layer
            * str -- alias of next layer