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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 _select_md5sum_arch(self, md5sum, md5sum64):
 """Return checksums by arch """

        if md5sum and md5sum64:
            if self.meta.arch == "x86_64":
                return md5sum64
            else:
                return md5sum
        if md5sum:
            return md5sum
        else:
            return md5sum64