Note: Grid.Cell is now a dataclass instead of a namedtuple — could this be considered an API change?

Unfortunately it now complains about the type of Grid.Cell.data:

Type variable "T" has no meaning in this context

Copilot chat suggests:

One possible workaround is to define Cell as a separate class outside of Grid, and pass the type variable T as a parameter to both classes. Here's how you can do it:

@dataclasses.dataclass
class Cell(Generic[T]):
    index: int
    position: Position
    region: Region
    data: Optional[T]

class Grid(Generic[T]):
    # ...
    Cell: Type[Cell[T]]
    # ...

    def __init__(
        self,
        region: Region,
        cols: Optional[int] = None,
        rows: Optional[int] = None,
        data: Optional[Sequence[Sequence[T]]] = None,
    ):
        # ...
        self.Cell = Cell[T]

In this code, Cell is a generic class that takes a type variable T. The type of Cell.data is Optional[T], which means it can be either None or an instance of type T. When you create a Grid with a specific type, the Cell instances in that grid will also have data of that type.

Who knows if that'll work, but I won't bother.