What is the method resolution order (MRO)?
PICTURE THIS: OOP PILLARS
Simple meaning
MRO is the linear order Python uses to find attributes on a class and its bases.
WHY — OOP instead of guessing?
Why interviewers care about OOP:
who only read docs from people who shipped.
and tied to Python work.
Name the idea, why it exists, then one short example.
End with when you use it and one common pitfall.
STEPS — What happens step by step?
Before you speak the answer, walk the interviewer through these steps:
- 1MRO is the linear
order Python uses to find attributes on a class and its bases.
- 2Why it exists
CPython uses C3 linearization
- 3inspect it with Class.__mro__
or Class.mro().
- 4super() follows this order,
which is why cooperative multiple inheritance works when every class calls super().
- 5Common mistake
What juniors usually get wrong.
- 6Close
When you pick this over the alternative.
EXAMPLE — See it in action
Here's a short line you can speak, broken into clear beats:
Note: Adapt this scaffold to your own project — keep it under 60–90 seconds.
Key takeaway
MRO is the linear order Python uses to find attributes on a class and its bases. CPython uses C3 linearization