title: Python: Strip Everything but Numbers
body: <p>I have to extract a number (a measured time value) from each of several strings. How could I do this elegantly? All numbers are positive and have a maximum of two decimal places. (E.g.: 2.3/ 40.09/ 101.4 - no numbers in E notation). The code I am looking for should do something like the following pseudocode: </p>
  
  <pre><code>&gt;&gt;&gt; "It took 2.3 seconds".strip(everything but ".1234567890")
  2.3
  </code></pre>