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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 _makeflags(self):
 """Set variable MAKEFLAGS with the numbers of processors """

        if self.meta.makeflags in ["on", "ON"]:
            cpus = multiprocessing.cpu_count()
            os.environ["MAKEFLAGS"] = "-j{0}".format(cpus)