Example of generating md5sums.

hashfile

def make_python_md5sum(filename):
  with open(filename, "rb") as instream:
      md5 = hashlib.md5()
      # for large files this might need to be a loop reading in
      # chunks. md5.update will work correctly when being given blocks
      block = instream.read()
      md5.update(block)
  return md5.hexdigest()