Python int hash, is that a feature or a bug for 'hash(int(-1))'?

Question

Python code:

print(hash(int(3)))
print(hash(int(2)))
print(hash(int(1)))
print(hash(int(0)))
print(hash(int(-1)))
print(hash(int(-2)))
print(hash(int(-3)))

Result:

3
2
1
0
-2
-2
-3

So result for this line looks suspicious:

print(hash(int(-1)))

Is that a feature or a bug?