why sometimes the python interpreter can't recognize the up arrow key?
<p>This question troubled me for really for a long time, and I can't figure out the answer all the time.</p>

<p>I have various versions of python in my ubuntu. Some versions of python's interpreter can 
recognize keyboard arrow keys normally. But some versions can't.</p>

<p>For example. In my python2.6 interpreter, all keyboard keys can be read properly. 
But in my python2.7 interpreter, if I type "up arrow key" on my keyboard, the interpreter will show this, what I want is to reappear <code>&gt;&gt;&gt; test = "hello world"</code>:</p>

<pre><code>(python2.7)yarkee@yarkee-laptop:~$ python
Python 2.7.3 (default, Mar 19 2013, 19:57:37) 
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
&gt;&gt;&gt; test = "hello world"
&gt;&gt;&gt; ^[[A
</code></pre>
