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when trying to facilitate expand function to a FastAPI endpoint using relationships get a "cyclic reference" error.

when the user defines expand=parents, we expand only the first layer, where all parents and children will have to count on how many relations they have on each. which works well

What I want to achieve is when parents.parents is defined, or any combination of these to expand the nested layers. expand can be any combination of XXX.YYY.XXX...

I have written a helper_function only to include data up until the level requested by user using SQL alchemy relationships

using pydantic 2.0.3 pydantic_core 2.3.0 fastapi 0.110.0

example pydantic Schema

from typing import Optional, List, Union
Person(BaseModel):
    id: int
    name: str
    parents: Optional[Union[List['Person'], int]] = None
    children: Optional[Union[List['Person'], int]] = None
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    if Person's attribute parents is of type list, how can that attribute also have its own parents attribute? Can you please provide a reproducible example of code you want to execute, with a clear description of the output you wish to obtain, and what output you are obtaining instead? Commented Jun 22, 2024 at 22:02
  • idea is Person C, can have Person A and B as its parents and Persons D and E as Children. who are all Person ( or humans ) the relationship is linked via a relationship table where there could be entries of parant_id and child_id. Person table parents and children are back_populate fields which help with the SQL alchemy expand. Commented Jun 23, 2024 at 7:17
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