title: Extract string with Python re.match
body: <pre><code>import re
  str="x8f8dL:s://www.qqq.zzz/iziv8ds8f8.dafidsao.dsfsi"
  
  str2=re.match("[a-zA-Z]*//([a-zA-Z]*)",str)
  print str2.group()
  
  current result=&gt; error
  expected =&gt; wwwqqqzzz
  </code></pre>
  
  <p>I want to extract the string <code>wwwqqqzzz</code>.  How I do that? </p>
  
  <p>Maybe there are a lot of dots, such as: </p>
  
  <pre><code>"whatever..s#$@.d.:af//wwww.xxx.yn.zsdfsd.asfds.f.ds.fsd.whatever/123.dfiid"
  </code></pre>
  
  <p>In this case, I basically want the stuff bounded by <code>//</code> and <code>/</code>.  How do I achieve that?</p>
  
  <p>One additional question:</p>
  
  <pre><code>import re
  str="xxx.yyy.xxx:80"
  
  m = re.search(r"([^:]*)", str)
  str2=m.group(0)
  print str2
  str2=m.group(1)
  print str2
  </code></pre>
  
  <p>Seems that <code>m.group(0)</code> and <code>m.group(1)</code> are the same.</p>