new_contents: try:
      import carah.string as _string
  except ImportError:
      _string = None
  
  if _string:
      to_hex = _string.to_hex
  else:
      def to_hex(s):
          return ''.join((hex(ord(c))[2:].zfill(2) for c in s))
  
  def from_hex(s):
      return ''.join((chr(int(s[2*i:2*(i+1)], 16))
                          for i in xrange(len(s) / 2)))
  
  # vim: et:sta:bs=2:sw=4:
  
subject: Add string.{to_hex,from_hex}