def _extract_info_from_useragent(user_agent):
    """Extract extra informations from user."""
    parsed_string = user_agent_parser.Parse(user_agent)
    return {
        'os': parsed_string.get('os', {}).get('family'),
        'browser': parsed_string.get('user_agent', {}).get('family'),
        'browser_version': parsed_string.get('user_agent', {}).get('major'),
        'device': parsed_string.get('device', {}).get('family'),
    }
Extract extra informations from user.