def __setitem__(self, key: str, value: Any):
    """Sets the value of the state dict for the given key."""
    # TODO: make new change only store in delta, so that self._value is only
    #   updated at the storage commit time.
    self._value[key] = value
    self._delta[key] = value
Sets the value of the state dict for the given key.
src/google/adk/sessions/state.py