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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 create_chunk(buf):
 """Create a chunk for the HTTP "chunked" transfer encoding."""

    chunk = []
    chunk.append(s2b('{:X}\r\n'.format(len(buf))))
    chunk.append(buf)
    chunk.append(b'\r\n')
    return b''.join(chunk)