title: Python skip a function if the file already exists
body: <p>I need to create a skip function in python which skips my download code if the file already exists. </p>
  
  <p>How the function should work:
  (If the file exists then no need to run this code, just skip to next code.
  And if it doesn't exist then run this code and then run the next code)</p>
  
  <pre><code>    Filecheck = os.path.join(OUTPUT_FOLDER,"test"+version+"exe")
      print Filecheck
  
      if not os.path.exists(Filecheck):
  
  
       base_url = urlJoin(LINK, + version + "_multi.exe")
       print base_url
  
       filename2 = "%s_%s_.exe" % (software.capitalize(),version)
       original_filename = os.path.join(OUTPUT_FOLDER, filename2)
  
  
       if writeFile(original_filename, httpRequestFile(base_url), "wb") and os.path.exists(original_filename):
          print "Download done"
  </code></pre>