A Why & how question

Question

def f (m,n)
return m|n
print (f(10,20)

why it is 30 ?
how does it work ?

Answer 1

Just in case you didn't get @Petr Leliaev's explanation:

Binary OR operation is performed based on the two numbers passed into the function. The two numbers are evaluated in binary format.

OR
0|0 = 0
0|1 = 1
1|0 = 1
1|1 = 1

10 (decimal) is 1010 (binary).
20 (decimal) is 10100 (binary).

01010
10100
----------
11110 = 30
----------

Answer 2

m=10=1010(2)
n=20=10100(2)
m|n = 11110(2)=30(10)