Merge pull request yidao620c#75 from 0x4ec7/patch-4

yidao620c · yidao620c · commit 3c0dca10fc23 · 2016-01-11T11:37:54.000+08:00
修改代码错误
diff --git a/source/c04/p01_manually_consuming_iterator.rst b/source/c04/p01_manually_consuming_iterator.rst
@@ -32,7 +32,7 @@
 
     with open('/etc/passwd') as f:
         while True:
-            line = next(f)
+            line = next(f, None)
             if line is None:
                 break
             print(line, end='')
