Why does using setdefault on a dictionary in python print it out?

Question

I'm on Windows, using the PyCharm IDE's terminal to ssh into a linux server, on that server I'm using python interactively. When I update a dictionary with a value, the terminal outputs the value back to me:

>>> x={}
>>> x.setdefault("y",0)
0

I can't figure out why this is happening. I've never noticed that behavior before? I also tried to ssh directly with the Windows 10 terminal but the same thing happens, so it's not PyCharm specific.

I just don't want the visual clutter of it throwing a value back at me every time I try to set up a dictionary. What could be making it do this? It's the first time I login through Windows so I feel like this is somehow the culprit?

[Official documentation](https://docs.python.org/3/library/stdtypes.html#dict.setdefault) — Andrej Kesely, May 07 '21 at 20:12

score 0 · Answer 1 · answered May 07 '21 at 20:14

0

It's not windows specific."setdefault" returns the value of key also you are using python in interactive mode you will get the returned value. you can assign it to variable.

answered May 07 '21 at 20:14

Poonam Adhav

382
3
10

Alexander Sica · Accepted Answer · 2021-05-07T20:28:28.940

0

Thymine!

This is the expected behavior, as you can see in the documentation

setdefault(key[, default])

If key is in the dictionary, return its value. If not, insert key with a value of default and return default. default defaults to None.

Maybe this can help you too

edited May 07 '21 at 20:28

answered May 07 '21 at 20:19

Alexander Sica

51
4

Is there a way to set a default value without having it returned? I can't seem to find one – Thymine May 07 '21 at 20:24
assign it to variable c = x.setdefault("y", 0) so c is noting but throwaway variable. – Poonam Adhav May 07 '21 at 20:27
I edited my answer adding the following link: https://stackoverflow.com/questions/9139897/how-to-set-default-value-to-all-keys-of-a-dict-object-in-python – Alexander Sica May 07 '21 at 20:31

Why does using setdefault on a dictionary in python print it out?

2 Answers2