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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 openstack_upgrade_available(package):
 """ Determines if an OpenStack upgrade is available from installation source, based on version of installed package. :param package: str: Name of installed package. :returns: bool: : Returns True if configured installation source offers a newer version of package. """


    import apt_pkg as apt
    src = config('openstack-origin')
    cur_vers = get_os_version_package(package)
    if not cur_vers:
        # The package has not been installed yet do not attempt upgrade
        return False
    if "swift" in package:
        codename = get_os_codename_install_source(src)
        avail_vers = get_os_version_codename_swift(codename)
    else:
        avail_vers = get_os_version_install_source(src)
    apt.init()
    return apt.version_compare(avail_vers, cur_vers) >= 1