How nested "in" evaluated in python

Question

l = [1, True, 'a']
print(1 in l in l) # outputs False
print((1 in l) in l) # outputs True

Why it gives False for first statment even though they are equivalent

Answer 1

They are not equivalent, and this is not nesting.
It is called "operator chaining".

x in y in z

is the same as:

(x in y) and (y in z)

similar to: x < y < z

https://www.geeksforgeeks.org/chaining-comparison-operators-JUMP_LINK__&&__python__&&__JUMP_LINK/

Unrelated note: never use lowercase L or uppercase i as variable name, it is too confusing even in monospace font.

Answer 2

Thank you sir