function createAuction(
        uint256 _tokenId,
        uint256 _price,
        address _seller
    )
        external
        whenNotPaused
        canBeStoredWith128Bits(_price)
    {
        require(_owns(msg.sender, _tokenId));
        _escrow(msg.sender, _tokenId);
        Auction memory auction = Auction(
            _seller,
            uint128(_price),
            uint64(now)
        );
        _addAuction(_tokenId, auction);
    }