code: def _import_next_layer(self, proto, length):
          
          if self._exproto == 'null' and self._exlayer == 'None':
              from pcapkit.protocols.raw import Raw as NextLayer
          else:
              from pcapkit.foundation.analysis import analyse as NextLayer
          # from pcapkit.foundation.analysis import analyse as NextLayer
          if length == 0:
              next_ = NoPayload()
          elif self._onerror:
              next_ = beholder_ng(NextLayer)(self._file, length, _termination=self._sigterm)
          else:
              next_ = NextLayer(self._file, length, _termination=self._sigterm)
          return next_
docs: 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