Comment 3 for bug 1577731

Attached is a stripped down sample of what shaker does:

(venv) ubuntu@x1:~$ OS_PASSWORD=test python test.py
Pass is "test"

(venv) ubuntu@x1:~$ OS_PASSWORD=te\$st python test.py
Traceback (most recent call last):
  File "test.py", line 17, in <module>
    conf.log_opt_values(LOG, std_logging.DEBUG)
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 2517, in log_opt_values
    _sanitize(opt, getattr(self, opt_name)))
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 2183, in __getattr__
    raise NoSuchOptError(name)
oslo_config.cfg.NoSuchOptError: no such option in group DEFAULT: os_password
(venv) ubuntu@x1:~$ OS_PASSWORD=test python test.py --os-password=over
Pass is "over"

(venv) ubuntu@x1:~$ OS_PASSWORD=test python test.py --os-password=ov\$er
Traceback (most recent call last):
  File "test.py", line 16, in <module>
    conf(project='test')
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 2162, in __call__
    else sys.argv[1:])
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 2754, in _parse_cli_opts
    return self._parse_config_files()
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 2773, in _parse_config_files
    self._validate_cli_options(namespace)
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 2786, in _validate_cli_options
    value = self._substitute(value, group=group, namespace=namespace)
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 2652, in _substitute
    self.StrSubWrapper(self, group=group, namespace=namespace))
  File "/usr/lib/python2.7/string.py", line 207, in safe_substitute
    return self.pattern.sub(convert, self.template)
  File "/usr/lib/python2.7/string.py", line 198, in convert
    return '%s' % (mapping[named],)
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 3035, in __getitem__
    value = self.conf._get(key, namespace=self.namespace)
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 2567, in _get
    value = self._do_get(name, group, namespace)
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 2584, in _do_get
    info = self._get_opt_info(name, group)
  File "/home/ubuntu/venv/local/lib/python2.7/site-packages/oslo_config/cfg.py", line 2718, in _get_opt_info
    raise NoSuchOptError(opt_name, group)
oslo_config.cfg.NoSuchOptError: no such option in group DEFAULT: er