Use undefined variable in master_relation_broken

master_relation_broken() is possible to use undefined value "PASSWORD".

http://bazaar.launchpad.net/~charmers/charms/trusty/jenkins/trunk/view/head:/hooks/jenkins_hooks.py#L199

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def master_relation_broken():
    password = config('password')
    if not password:
        passwd_file = os.path.join(JENKINS_HOME, '.admin_password')
        with open(passwd_file, 'w+') as fd:
            PASSWORD = fd.read()

    for member in relation_ids():
        member = member.replace('/', '-')
        log("Removing node %s from Jenkins master." % (member), level=DEBUG)
        del_node(member, config('username'), PASSWORD) <-- if set password, PASSWORD is undefined?
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