title: How can I determine the largest integer value in a string?
body: <p>Here is what I have:</p>
  
  <pre><code>largest_int=None
  
  def largest_digit(string_one):
      for ch in string_one:
          if not string_one.isdigit():
              largest_int=None
          elif ch in string_one.isdigit():
              largest_int=ch&gt;ch
              print (largest_int)
  
  largest_digit('Hello 1 2 3 5 4')
  </code></pre>
  
  <p>I'm trying to tell python to pull the integers from a string and print the largest one.  My code isn't working however, and I would appreciate any help with fixing it without using something like import re. </p>