title: Python: binascii.a2b_hex gives "Odd-length string"
body: <p>I have a hex value that I'm grabbing from a text file, then I'm passing it to a2b_hex to convert it to the proper binary representation.  Here is what I have:</p>
  
  <pre><code>k = open('./' + basefile + '.key', 'r')
  k1 = k.read()
  k.close()
  my_key = binascii.a2b_hex(k1)
  </code></pre>
  
  <p>When I print k1, it is as expected: 81e3d6df</p>
  
  <p>Here is the error message:</p>
  
  <pre><code>Traceback (most recent call last):
    File "xor.py", line 26, in &lt;module&gt;
      my_key = binascii.a2b_hex(k1)
  TypeError: Odd-length string
  </code></pre>
  
  <p>Any suggestions?  Thanks!</p>