def tensor_init_context(self) -> AbstractContextManager:
        """Controls how tensors get created (device, dtype)."""
        precision_init_ctx = self.precision.tensor_init_context()
        stack = ExitStack()
        stack.enter_context(self.root_device)
        stack.enter_context(precision_init_ctx)
        return stack
Controls how tensors get created (device, dtype).
src/lightning/fabric/strategies/strategy.py