Python assign dictionary value in a constructor

Question

Please look at the below code.

signal = {
    "id": "p752",
}

class Trigger:
    def __init__(self, signal):
        self.id = signal['id'],
        
        print(type(signal['id']))
        print(type(self.id))
    
    def get_trigger(self):
        print(self.id)


t1 = Trigger(signal)
t1.get_trigger()

The output I get is

<class 'str'>
<class 'tuple'>
('p752',)

I honestly don't know what is happening here. When I assign signal['id'] to 'id' inside the constructor why is changing to a tuple?

`self.id = signal['id'],` has a trailing comma, which makes that a tuple. This appears to be a typo, so I voted to close it as such. — Carcigenicate, Aug 20 '20 at 00:26
`signal['id'],` is a tuple. `signal['id']` (no comma) is not a tuple. So change `self.id = signal['id'],` to `self.id = signal['id']` — Steven Rumbalski, Aug 20 '20 at 00:28

hedy · Answer 1 · 2020-08-20T01:18:25.090

0

self.id = signal['id']

Trailing comma is to be removed so it is treated as a tuple

edited Aug 20 '20 at 01:18

answered Aug 20 '20 at 00:31

hedy

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I feel so stupid. Thanks. – codeyashu Aug 20 '20 at 01:09

Python assign dictionary value in a constructor

1 Answers1