from typing import List


def filter_dict(_dict: dict, *keys: List[object]) -> dict:
    """ Apply a simple filter over a given dictionary
        Usage:
            >>> filter_dict({'a': 1, 'b': 2, 'c':3}, 'a', 'c')
            >>> {'a': 1, 'c': 3}
    """
    filters = keys
    if isinstance(keys[0], list):
        filters = keys[0]
    return {k: v for k, v in _dict.items() if k in filters}