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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 extractSNPs(snpsToExtract, options):
 """Extract markers using Plink. :param snpsToExtract: the name of the file containing markers to extract. :param options: the options :type snpsToExtract: str :type options: argparse.Namespace :returns: the prefix of the output files. """

    outPrefix = options.out + ".pruned_data"
    plinkCommand = ["plink", "--noweb", "--bfile", options.bfile, "--extract",
                    snpsToExtract, "--make-bed", "--out", outPrefix]
    runCommand(plinkCommand)
    return outPrefix