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python - OrderedDict does not preserve the order

from collections import OrderedDict
import pprint

menu = {"about" : "about", "login" : "login", 'signup': "signup"}

menu = OrderedDict(menu)
pprint.pprint(menu.items())

import sys
sys.exit()

The output is:

[('about', 'about'), ('signup', 'signup'), ('login', 'login')]

So, the order is not preserved even with the use of OrderedDict. I know the dictionaries don't preserve the initial order by default, and all those things. But I want to learn why the OrderedDict is not working.

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By putting the items in a (non-ordered) dict and constructing the OrderedDict from that, you've already discarded the original order. Construct the OrderedDict from a list of tuples, not a dict.


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