title: python os.rename ""cannot create a file when that file already exists
body: <p>K.. I'm just using a simple script I found here:</p>
  
  <pre><code>import os
  from os import rename, listdir
  
  print os.listdir(".")
  for filename in os.listdir("."):
      if filename.startswith("colon-"):
          print filename
          os.rename(filename, filename[7:])
  </code></pre>
  
  <p>I need to basically take all files like colon-21.mp3 converted to 21.mp3.</p>
  
  <p>But I get the error <code>CANNOT CREATE A FILE WHEN THAT FILE ALREADY EXISTS.</code>
  How does one solve this? I am using Windows 7.</p>