    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
    /**
     * @dev Pauses all functions affected by `whenNotPaused`.
     */
    function pause() public onlyOwner {
        _pause();
    }

    /**
     * @dev Unpauses all functions affected by `whenNotPaused`.
     */
    function unpause() public onlyOwner {
        _unpause();
    }
