[Python] Subclassing random.Random produces different results with same seed

I've run into something I don't understand. This code:

import random


class MyRandom(random.Random):
pass


r = random.Random()
r.seed(10)
print(r.randint(0, 20))
print(r.randint(0, 20))
print(r.randint(0, 20))

print("------------")

r2 = MyRandom()
r2.seed(10)
print(r2.randint(0, 20))
print(r2.randint(0, 20))
print(r2.randint(0, 20))



...prints:

18
1
13
------------
18
1
13


This is as expected, since it's the same seed. But if I innocuously override the random() method like this:

import random



class MyRandom(random.Random):

def random(self):
return super().random()



r = random.Random()
r.seed(10)
print(r.randint(0, 20))
print(r.randint(0, 20))
print(r.randint(0, 20))

print("------------")
r2 = MyRandom()
r2.seed(10)
print(r2.randint(0, 20))
print(r2.randint(0, 20))
print(r2.randint(0, 20))


Suddenly it prints:

18
1
13
------------
20
9
6


Why on earth would that change anything? How is the call to super somehow upsetting the internal state?

Even weirder, there isn't a discrepancy if I'm calling r.random() instead of r.randint(). Perhaps that clue will be helpful.

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