code: def p_andnode_expression(self, t):
      '''andnode_expression : LB  identlist RB '''
      self.accu.add(Term('vertex', ["and(\""+t[2]+"\")"]))
      t[0] = "and(\""+t[2]+"\")f p_andnode_expression(self, t):
      '''andnode_expression : LB  identlist RB '''
      self.accu.add(Term('vertex', ["and(\""+t[2]+"\")"]))
      t[0] = "and(\""+t[2]+"\")"
docs: andnode_expression : LB  identlist RB