new_contents: """Read a binary file in chunks, using 'modern' idiomatic Python."""
  import functools
  
  CHUNKSIZE = 42
  
  with open(__file__, 'rb') as handle:
      read_chunk = functools.partial(handle.read, CHUNKSIZE)
      for i, chunk in enumerate(iter(read_chunk, b'')):
          print('{:5d} {!r}'.format(i + 1, chunk))
  
subject: Read a binary file in chunks, using 'modern' idiomatic Python