added chapter map to README

17-it-generator/sentence.py

@@ -0,0 +1,24 @@
+"""
+Sentence: access words by index
+"""
+
+import re
+import reprlib
+
+RE_WORD = re.compile(r'\w+')
+
+
+class Sentence:
+
+    def __init__(self, text):
+        self.text = text
+        self.words = RE_WORD.findall(text)  # <1>
+
+    def __getitem__(self, index):
+        return self.words[index]  # <2>
+
+    def __len__(self, index):  # <3>
+        return len(self.words)
+
+    def __repr__(self):
+        return 'Sentence(%s)' % reprlib.repr(self.text)  # <4>