title: Python string search efficiency
body: <p>For very large strings (spanning multiple lines) is it faster to use Python's built-in string search or to split the large string (perhaps on <code>\n</code>) and iteratively search the smaller strings?</p>
  
  <p>E.g., for very large strings:</p>
  
  <pre><code>for l in get_mother_of_all_strings().split('\n'):
   if 'target' in l:
     return True
  return False
  </code></pre>
  
  <p>or</p>
  
  <pre><code>return 'target' in get_mother_of_all_strings()
  </code></pre>