python - Pythonで多次元配列を初期化するには?

Question

これが重複した質問である場合は申し訳ありませんが、同様の例がどこにも見つからなかったので、助けを求めてください。

lookup = {}

# These values will be filled by DB lookup service at runtime
# Maximum array length for category is unknown before program start 
# Format [Lookup Category], [Lookup Key], Lookup Id

lookup['name']['John'] = 1
lookup['name']['Jane'] = 2
lookup['name']['Joe'] = 3
lookup['gender']['Male'] = 1
lookup['gender']['Female'] = 2
lookup['country']['Japan'] = "jp"
lookup['country']['China'] = "ch"

print lookup['name']['Jane']
print lookup['gender']['Female']
print lookup['country']['China']

Answer 1

おそらくcollections.defaultdictが必要です

例えば

from collections import defaultdict

lookup = defaultdict(dict)
lookup['name']['John'] = 1
lookup['name']['Jane'] = 2
lookup['name']['Joe'] = 3
lookup['gender']['Male'] = 1
lookup['gender']['Female'] = 2
lookup['country']['Japan'] = "jp"
lookup['country']['China'] = "ch"

print lookup['name']['Jane']
print lookup['gender']['Female']
print lookup['country']['China']