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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 split_namedpipe_cls(pair1_file, pair2_file, data):
 """Create a commandline suitable for use as a named pipe with reads in a given region. """

    if "align_split" in data:
        start, end = [int(x) for x in data["align_split"].split("-")]
    else:
        start, end = None, None
    if pair1_file.endswith(".sdf"):
        assert not pair2_file, pair2_file
        return rtg.to_fastq_apipe_cl(pair1_file, start, end)
    else:
        out = []
        for in_file in pair1_file, pair2_file:
            if in_file:
                assert _get_grabix_index(in_file), "Need grabix index for %s" % in_file
                out.append("<(grabix grab {in_file} {start} {end})".format(**locals()))
            else:
                out.append(None)
        return out