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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 repository_url_part(distro):
 """ Historically everything CentOS, RHEL, and Scientific has been mapped to `el6` urls, but as we are adding repositories for `rhel`, the URLs should map correctly to, say, `rhel6` or `rhel7`. This function looks into the `distro` object and determines the right url part for the given distro, falling back to `el6` when all else fails. Specifically to work around the issue of CentOS vs RHEL:: ('Red Hat Enterprise Linux Server', '7.0', 'Maipo') """

    if distro.normalized_release.int_major >= 6:
        if distro.normalized_name == 'redhat':
            return 'rhel' + distro.normalized_release.major
        if distro.normalized_name in ['centos', 'scientific', 'oracle', 'virtuozzo']:
            return 'el' + distro.normalized_release.major

    return 'el6'