How to make sure that a class is subclass of another?

[Kludex]

Hi there 👋

I'm looking to find the best design for my codemod.

The problem statement is: I need to replace the method dict() to model_dump() on every class that is subclass of BaseModel.

For example, the following code:

from pydantic import BaseModel

class MyBaseModel(BaseModel):
   ...
   
class Potato(MyBaseModel):
   def dict():
      ...

Needs to become:

from pydantic import BaseModel

class MyBaseModel(BaseModel):
   ...
   
class Potato(MyBaseModel):
   def model_dump():
      ...

And I'm working with a VisitorBasedCodemodCommand, as you can see here.

What I guess I should do... Is to iterate over all classes with a visitor, and save the information of the base classes of a class, and then do the normal match on the codemod itself. Assuming this is correct, where should this visitor live? In the __init__() on the codemod? Or...? If my assumption is wrong, what would be the right way to do this?