new_contents: import os
  import subprocess
  
  factoid = 'nodejs_version'
  
  def fact():
      '''Returns the Node.js version if installed'''
      version = 'None'
      binary = '/usr/local/bin/node'
      if os.path.exists(binary):
          try:
              cmd = [binary, '--version']
              proc = subprocess.check_output(cmd)
              version = proc[1:].strip()
          except:
              pass
  
      return {factoid: version}
  
  if __name__ == '__main__':
      print '<result>%s</result>' % fact()[factoid]
  
subject: Add Node.js version detection