@staticmethod
def _get_my_optional_vals(results, *items):
    """
        Get results[key] if key in results, return a list.
        valid *items*: [(key, class or (cls1, cls2), default_val), ...]
            class: str, int, float, list, dict, ...
        """
    vals = []
    for key, cls, default in items:
        _val = results.get(key, default)
        if not isinstance(_val, cls):
            _val = default
        vals.append(_val)
    return vals
