python dictionary append
list.append returns None , since it is an in-place operation and you are assigning it back to dates_dict[key] . So, the next time when you do dates_dict.get(key, []).append you are actually doing None.append . That is why it is failing. Instead, you can , Just use append: list1 = [1, 2, 3, 4, 5] list2 = [123, 234, 456] d = 'a': [], 'b': []} d['a'].append(list1) d['a'].append(list2) print d['a'].
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 python dictionary append 相關參考資料
5. Data Structures — Python 3.4.8 documentation
You can't use lists as keys, since lists can be modified in place using index assignments, slice assignments, or methods like append() and extend() . It is best to think of a dictionary as an unor... https://docs.python.org Appending to list in Python dictionary - Stack Overflow
list.append returns None , since it is an in-place operation and you are assigning it back to dates_dict[key] . So, the next time when you do dates_dict.get(key, []).append you are actually doing Non... https://stackoverflow.com Appending values to dictionary in Python - Stack Overflow
Just use append: list1 = [1, 2, 3, 4, 5] list2 = [123, 234, 456] d = 'a': [], 'b': []} d['a'].append(list1) d['a'].append(list2) print d['a']. https://stackoverflow.com Design2U » [python] List (串列) 與dictionary (字典) 基本指令
在python 中沒有陣列，一般都是用dictionary 這種東西來取代之每次都很容易搞混這兩個東西，這篇文章把它們兩個的指令好好整理一下. List 部份(順序固定) # 起始化list. L1= 'I':1,'II':2,'III':3,'IV':4,'V':5,'VI':6,'VII&... http://design2u.me python - How to add key,value pair to dictionary? - Stack Overflow
Add a key, value pair to dictionary aDict = } aDict[key] = value. What do you mean by dynamic addition. https://stackoverflow.com python: Appending a dictionary to a list - I see a pointer like ...
You are correct in that your list contains a reference to the original dictionary. a.append(b.copy()) should do the trick. Bear in mind that this makes a shallow copy. An alternative is to use copy.d... https://stackoverflow.com Python: How to append to existing key of a dictionary? - Stack ...
You're appending to the value (which is a list in this case), not the key. myDict['games'].append(...). https://stackoverflow.com |