class_docstr: A list of words, augmented by an attribute ``num`` used to record
  the sentence identifier (the ``n`` attribute from the XML).
code: def __init__(self, num, items):
      self.num = num
      list.__init__(self, items)
  
imports: from nltk.corpus.reader.api import *
  from nltk.corpus.reader.xmldocs import XMLCorpusReader, XMLCorpusView
  from nltk.tree import Tree
label_desc: Use image node_id 1 to create a new SemcorSentence object from inherited base classes: list with example: obj = SemcorSentence(num, items)