ch17: update from book draft

17-it-generator/sentence.py

@@ -1,7 +1,18 @@
 """
 Sentence: access words by index
+
+    >>> text = 'To be, or not to be, that is the question'
+    >>> s = Sentence(text)
+    >>> len(s)
+    10
+    >>> s[1], s[5]
+    ('be', 'be')
+    >>> s
+    Sentence('To be, or no... the question')
+
 """
 
+# tag::SENTENCE_SEQ[]
 import re
 import reprlib
 
@@ -17,8 +28,10 @@ class Sentence:
     def __getitem__(self, index):
         return self.words[index]  # <2>
 
-    def __len__(self, index):  # <3>
+    def __len__(self):  # <3>
         return len(self.words)
 
     def __repr__(self):
         return 'Sentence(%s)' % reprlib.repr(self.text)  # <4>
+
+# end::SENTENCE_SEQ[]