Writing a "Raw" Image to a File (Win, PIL)

[W. eWatson]

I have an image of described as:
Img Info:  {}
  size:  (640, 480)
  format:  None
  mode:  P
  palette:  <ImagePalette.ImagePalette instance at 0x02393378>
  bands:  ('P',)
  type:  <type 'instance'>

I'd like to write it to a file. Apparently, I need to convert it to a string 
first. How do I do that? Pickle?
-- 
                                W. eWatson

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