In this code, Why line no. 4 is valid in python???

Question

https://code.sololearn.com/cphc9KzsIOz3/?ref=app

Answer 1

It is not decrementing the value of "a" at all.

It is just reversing the sign of "a" twice and then assigning that value to "b"

You can assume it to be like this:-
b = -(-a)
Which is same as b = a

Answer 2

Thanks! Arsenic and Avinash Kumar

Answer 3

@Arsenic is saying correctly