How a single parenthesis could change the output?

Question

print(3 in [1, 2, 3] == [1, 2, 3])
#Output: True 

print((3 in [1, 2, 3]) == [1, 2, 3])
#Output: False

I'm just wondering what is happening here.

score 2 · Accepted Answer · answered Jan 25 '22 at 17:17

2

Because of Python's comparison chaining feature.

3 in [1, 2, 3] == [1, 2, 3]

is treated as

(3 in [1, 2, 3]) and ([1, 2, 3] == [1, 2, 3])

answered Jan 25 '22 at 17:17

Barmar

1

Are you familiar with `1 < variable < 10`? It's the same thing. – Barmar Jan 25 '22 at 17:33
Wait, what !? Isn't it same as `1 < variable and variable < 10` how you guys just do these things? That's really nice way to understand this concept. – Python learner Jan 25 '22 at 17:39
1

Yes, it's the same as that. What's surprising is that `in` is considered similar to ` – Barmar Jan 25 '22 at 17:46

1 Answers1