What problem does this fix? More helpful PR descriptions may help this get merged.

What problem does this fix? More helpful PR descriptions may help this get merged.

Type checker throw partially unknown error when used in strict mode (Pylance)
When I locally edited that line, everything was correct

origin: sqlmodel.main.Field
info: Column expected an argument

339 |    sa_column: Union[Column, UndefinedType] = Undefined,  # type: ignore

proposed change

339 |    sa_column: Union[Column[Any], UndefinedType] = Undefined,

If you want to see it yourself (be sure to set the type checker to strict)

import sqlmodel

class TestModel(sqlmodel.SQLModel, table=True):
    value: list[int] = sqlmodel.Field(sa_column=sqlmodel.Column(sqlmodel.JSON))

There is a better change, but it is not possible because Column was defined in sqlalchemy

# sqlalchemy.sql.schema
113 |    _T = TypeVar("_T", bound="Any", default="Any")  # python >= 3.13