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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 construct_makeblastdb_cmd( filename, outdir, blastdb_exe=pyani_config.MAKEBLASTDB_DEFAULT ):
 """Returns a single makeblastdb command. - filename - input filename - blastdb_exe - path to the makeblastdb executable """

    title = os.path.splitext(os.path.split(filename)[-1])[0]
    outfilename = os.path.join(outdir, os.path.split(filename)[-1])
    return (
        "{0} -dbtype nucl -in {1} -title {2} -out {3}".format(
            blastdb_exe, filename, title, outfilename
        ),
        outfilename,
    )