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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def _feed_stream(feeder, in_stream, out_stream, block_size = BLOCK_SIZE):
    'Uses feeder to read and convert from in_stream and write to out_stream.'

    while True:
        chunk = in_stream.read(block_size)
        if not chunk:
            break
        converted = feeder.feed(chunk)
        out_stream.write(converted)
    converted = feeder.feed()
    out_stream.write(converted)