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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 get_packagers_of_package(config, package):
 """ Retrieve the list of users who have commit on a package. :arg config: a dict containing the fedmsg config :arg package: the package you are interested in. :return: a set listing all the fas usernames that have some ACL on package. """


    if not _cache.is_configured:
        _cache.configure(**config['fmn.rules.cache'])

    key = cache_key_generator(get_packagers_of_package, package)
    creator = lambda: _get_pkgdb2_packagers_for(config, package)
    return _cache.get_or_create(key, creator)