code: def decode(self, s, triples=False):
          
          try:
              if triples:
                  span, data = self._decode_triple_conjunction(s)
              else:
                  span, data = self._decode_penman_node(s)
          except IndexError:
              raise DecodeError(
                  'Unexpected end of string.', string=s, pos=len(s)
              )
          top, nodes, edges = data
          return self.triples_to_graph(nodes + edges, top=top)
docs: Deserialize PENMAN-notation string *s* into its Graph object.
  
          Args:
              s: a string containing a single PENMAN-serialized graph
              triples: if True, treat *s* as a conjunction of logical triples
          Returns:
              the Graph object described by *s*
          Example:
  
              >>> codec = PENMANCodec()
              >>> codec.decode('(b / bark :ARG1 (d / dog))')
              <Graph object (top=b) at ...>
              >>> codec.decode(
              ...     'instance(b, bark) ^ instance(d, dog) ^ ARG1(b, d)',
              ...     triples=True
              ... )
              <Graph object (top=b) at ...>