title: Remove a prefix from a string
body: <p>I am trying to do the following, in a clear pythonic way:</p>
  
  <pre><code>def remove_prefix(str, prefix):
      return str.lstrip(prefix)
  
  print remove_prefix('template.extensions', 'template.')
  </code></pre>
  
  <p>This gives:</p>
  
  <pre><code>xtensions
  </code></pre>
  
  <p>Which is not what I was expecting (<code>extensions</code>). Obviously (stupid me), because I have used <a href="http://docs.python.org/2/library/string.html#string.lstrip">lstrip</a> wrongly: lstrip will remove all characters which appear in the passed <code>chars</code> string, not considering that string as a real string, but as "a set of characters to remove from the beginning of the string".</p>
  
  <p>Is there a standard way to remove a substring from the beginning of a string?</p>