Keeping a dictionary (or similar structure) ordered in Python-CodePudding

I need to work with two data structures that inherit all the properties of dictionaries in Python3.8. But I want these dictionaries to be ordered with respect to the key every time I insert an element. One dictionary has to keep an ascending order while the other a descending order.

For example, consider the two dictionaries

dic1 = {1:'a',2:'b',3:'c',5:'e'} #This dictionary needs to keep the order of ascending keys
dic2 = {5:'e', 3:'c',2:'b',1:'a'} #This dictionary needs to keep the order of ascending keys

and let's add an element to both of them

dic1[4]='d'
dic2[4]='d'

After these operations, I want the two dictionaries to be

> dic1 == {1:'a',2:'b',3:'c',4:'d',5:'e'} #This dictionary needs to keep the order of ascending keys
> True
> dic2 == {5:'e', 4:'d', 3:'c',2:'b',1:'a'} #This dictionary needs to keep the order of ascending keys
> True

without having to sort the dictionaries through dict(sorted(dic1)) or dict(sorted(dic2,reverse=True)).

I know that I can define dic1to be a SortedDictfrom sortedcontainers. However, in the documentation of sortedcontainers.SortedDictI cannot find how to define the order of the keys (ascending or descending).

Any insight?

CodePudding user response：

The documentation has exactly the example of what you're trying to do:

>>> sd = SortedDict(neg, enumerate('abc', start=1))
>>> sd
SortedDict(<built-in function neg>, {3: 'c', 2: 'b', 1: 'a'})

>>> keys = sd.keys()
>>> list(keys)
[3, 2, 1]