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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 set_buf_size(fd):
 """Set up os pipe buffer size, if applicable"""

    if OS_PIPE_SZ and hasattr(fcntl, 'F_SETPIPE_SZ'):
        fcntl.fcntl(fd, fcntl.F_SETPIPE_SZ, OS_PIPE_SZ)