async def modify_state(self, token: str) -> AsyncIterator[BaseState]:
        """Modify the state for a token while holding exclusive lock.

        Args:
            token: The token to modify the state for.

        Yields:
            The state for the token.
        """
        yield self.state()
Modify the state for a token while holding exclusive lock.

        Args:
            token: The token to modify the state for.

        Yields:
            The state for the token.
        
reflex/istate/manager.py