According to De Morgan law:

```
¬(P ˄ Q) ↔ (¬P) ˅ (¬Q)
¬(P ˅ Q) ↔ (¬P) ˄ (¬Q)

```

In Python 3.5 when I run:

```
A = True
B = True
x = not(A and B)==(not A) or (not B)
y = not(A or B)==(not A) and (not B)
print('x is :', x, '\ny is :' ,y)

```

This returns:

```
x is : True 
y is : False

```

Question: why y is False?