python - 如何将字典作为值添加到python中的键

Question

我有一个字典是-team={ludo:4,monopoly:5}

我怎样才能形成一个新的字典，它有一个名为board_gamesvalue 的键有另一个字典，它有一个键，上面的团队字典应该看起来像 -

new_team = { board_games : {junior:{ludo:4,monopoly:5}}}

基本上我正在尝试做一些类似 perlish 的事情 -

new_team['board_games']['junior'] = team

Answer 1

我看不到问题：

>>> team = {"ludo": 4, "monopoly": 5}
>>> new_team = {"board_games": {"junior": team}}
>>> new_team
{'board_games': {'junior': {'ludo': 4, 'monopoly': 5}}}

如果您想动态构建它，collections.defaultdict您需要的是：

>>> from collections import defaultdict
>>> new_dict = defaultdict(dict)
>>> new_dict['board_games']['junior'] = team
>>> new_dict
defaultdict(<type 'dict'>, {'board_games': {'junior': {'ludo': 4, 'monopoly': 5}}})

Answer 2

基本问题是，在您要编写的代码中尝试访问new_team['board_games']而不首先为其分配任何值。dict不支持。

如果您绝对坚持必须写new_team['board_games']['junior'] = team，那么有几种方法：

1）创建您需要的密钥：

new_team = { 'board_games' : dict() }
new_team['board_games']['junior'] = team

或许：

new_team = dict()
new_team['board_games'] = dict()
new_team['board_games']['junior'] = team

甚至：

new_team = dict();
new_team.setdefault('board_games', dict())
new_team['board_games']['junior'] = team

2）使用defaultdict：

import collections
new_team = collections.defaultdict(dict)
new_team['board_games']['junior'] = team