chapter06: Missed translation in python

chapter06/python.xml

@@ -138,9 +138,9 @@ tar --strip-components=1  \
     <title>Python 3 的内容</title>
 
     <segmentedlist>
-      <segtitle>Installed Programs</segtitle>
-      <segtitle>Installed Library</segtitle>
-      <segtitle>Installed Directories</segtitle>
+      <segtitle>安装的程序</segtitle>
+      <segtitle>安装的库</segtitle>
+      <segtitle>安装的目录</segtitle>
 
       <seglistitem>
         <seg>