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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 _localectl_set(locale=''):
    '''
    Use systemd's localectl command to set the LANG locale parameter, making
    sure not to trample on other params that have been set.
    '''
    locale_params = _parse_dbus_locale() if dbus is not None else _localectl_status().get('system_locale', {})
    locale_params['LANG'] = six.text_type(locale)
    args = ' '.join(['{0}="{1}"'.format(k, v) for k, v in six.iteritems(locale_params) if v is not None])
    return not __salt__['cmd.retcode']('localectl set-locale {0}'.format(args), python_shell=False)