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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 yum_install(**kwargs):
 """ installs a yum package """

    if 'repo' in kwargs:
        repo = kwargs['repo']

    for pkg in list(kwargs['packages']):
        if is_package_installed(distribution='el', pkg=pkg) is False:
            if 'repo' in locals():
                log_green(
                    "installing %s from repo %s ..." % (pkg, repo))
                sudo("yum install -y --quiet --enablerepo=%s %s" % (repo, pkg))
            else:
                log_green("installing %s ..." % pkg)
                sudo("yum install -y --quiet %s" % pkg)