[Python] Why is this an ambiguous MRO?

class First(object):
def __init__(self):
print("first")

class Second(First):
def __init__(self):
print("second")

class Third(First, Second):
def __init__(self):
print("third")


Source

Why can't Python create a consistent MRO? It seems to me it's pretty clear:

1. Search in First if method does not exist in Third
2. Search in Second if method does not exist in First

But if you try it out:

TypeError: Error when calling the metaclass bases
Cannot create a consistent method resolution
order (MRO) for bases First, Second

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