title: Check and wait until a file exists to read it
body: <p>I need to wait until a file is created then read it in. I have the below code, but sure it does not work:</p>
  
  <pre><code>import os.path
  if os.path.isfile(file_path):
      read file in
  else:
      wait
  </code></pre>
  
  <p>Any ideas please?</p>