title: Python regexp \w
body: <p>The <a href="https://docs.python.org/3.1/library/re.html" rel="nofollow noreferrer">Python manual</a> states: </p>
  
  <blockquote>
    <p>The special sequence \w for 8-bit (bytes) patterns matches characters 
    considered alphanumeric in the ASCII character set; this is equivalent to 
    [a-zA-Z0-9_].</p>
  </blockquote>
  
  <p>Compare now:</p>
  
  <pre><code>re.search(r"([\w]+)", 'München').group(1)
  </code></pre>
  
  <p>with:</p>
  
  <pre><code>re.search(r"([a-zA-Z0-9_]+)", 'München').group(1)  
  </code></pre>
  
  <p>The first statement outputs the whole city name München, the second only the first letter <code>M</code>. The letter <code>ü</code> is a single byte with code point <code>0xFC</code> = <code>252</code> (Latin-1). 
  My question is: assuming that the Python manual is correct, how can I reconcile the difference in output between <code>[\w]+</code> and <code>[a-zA-Z0-9_]+</code>  with the statement in the Python-3 manual? I use IDLE v. 3.6.2.</p>