`dict.fromkeys` without values as references to the same object

Question

I need to create a dictionary with Locks as values, but I can't use dict.fromkeys because it creates only one Lock and multiple references:

my_dict = dict.fromkeys(list_of_keys, Lock())

So I do it like:

my_dict = dict((my_key,Lock()) for my_key in list_of_keys)

But I wonder if it's possible to use dict.fromkeys in any way,

No, you can only use `dict.fromkeys()` if you want the same value in every element. — Barmar, Oct 29 '21 at 22:03
What is the actual problem you are trying to solve that you think you need `dict.fromkeys()` for? — Code-Apprentice, Oct 29 '21 at 22:10
Related: [How do I initialize a dictionary of empty lists in Python?](/q/11509721/4518341) — wjandrea, Oct 29 '21 at 22:12

wjandrea · Accepted Answer · 2021-10-29T22:13:16.537

0

It's not possible. dict.fromkeys() puts the same value (same object) for each element.

But at least, you could use a dict comprehension to make it look nicer:

my_dict = {my_key: Lock() for my_key in list_of_keys}

edited Oct 29 '21 at 22:13

answered Oct 29 '21 at 22:08

wjandrea

1 Answers1