```\nfunction openTrading() external onlyOwner() {\n    require(!tradingOpen,"trading is already open");\n    IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);\n    uniswapV2Router = _uniswapV2Router;\n    _approve(address(this), address(uniswapV2Router), _tTotal);\n    uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), _uniswapV2Router.WETH());\n    uniswapV2Router.addLiquidityETH{value: address(this).balance}(address(this),balanceOf(address(this)),0,0,owner(),block.timestamp);\n    swapEnabled = true;\n    cooldownEnabled = true;\n    _maxTxAmount = 50000000000000000 * 10**9;\n    tradingOpen = true;\n    IERC20(uniswapV2Pair).approve(address(uniswapV2Router), type(uint).max);\n}\n```\n