title: How to extract string after certain word in python?
body: <p>I am trying to get a reference number inside a string which is in most cases precedented by "Ref." or something similar.</p>
  
  <p>e.g.: </p>
  
  <blockquote>
    <p>Explorer II Ref.16570 Box</p>
  </blockquote>
  
  <p><a href="https://regex101.com/r/qO3NKM/3" rel="nofollow noreferrer">regex with further examples</a></p>
  
  <p>The problem is that there are many different variations<a href="https://regex101.com/r/qO3NKM/3" rel="nofollow noreferrer">1</a> as this is user generated content. How could I retrieve the number with python which is precented by e.g. <code>Ref.</code>? </p>
  
  <p>The number/string is not always the same pattern e.g. numbers. .They might be mixed with characters and dots and slashes but for a human eye there is almost always such a number in each line identifiable.</p>
  
  <p>E.g.:</p>
  
  <pre><code>Ref.16570
  Ref. 16570
  Referenz 216570
  Referenz 01 733 7653 4159-07 4 26
  331.12.42.51.01.002
  166.0173
  AB012012/BB01
  Ref. 167.021
  PAM00292
  14000M
  L3.642.4.56.6
  161.559.50
  801
  666
  753
  116400GV
  Ref.: 231.10.39.21.03.002
  3233
  Ref: 233.32.41.21.01.002
  T081.420.97.057.01
  16750
  ... almost each line in the example provided contains a certain ID
  </code></pre>
  
  <p>A small amount of false positives would not be a problem.</p>