solidity - 如何在我的智能合约中添加交易税（Bep20）

Question

我想添加一个交易税功能，收取发送者金额的 2.5% 以发送到所有者钱包地址。我该怎么做这个功能。

谢谢。

pragma solidity ^0.8.2;
contract Token  {
    
    mapping(address => uint) public balances;
    mapping(address => mapping(address => uint)) public allowance
    uint public totalSupply = 1,000,000,000,000 * 10 ** 18;  // Total supply and the smallest denomination
    string public name = "My Token"; // Name of Token
    string public = "TKN";  //Token Symbol  
    uint public decimal = 18; // Denoting smallest denomination and the number of decimals.(8 or 18)
    
    event Transfer(address indexed from , address indexed to ,uint value);
    
    constructor(){
        balances[msg.sender] = totalSupply;
        
    }
    //All the function names are required by the Bep20 standard
    function balanceOf(address owner) public view returns(uint){
        return balanceOf[owner];
        
    }
    
    function tranfser(address to , uint value) public returns(bool)
        require(balanceOf(msg.sender) >= value, 'balance is insufficient for transfer');
        balances[to] += value;
        balances[msg.sender] -= value;
        emit Transfer(msg.sender, to , value);
        return true;
        
        
        )
    function transferFrom(address from, address to ,uint value) public returns(bool){
        require (balanceOf(from) >= value, "balance is insufficient for transfer");
        require(allowance(from)[msg.sender] >= 'value',"allowance too low ")  ;
        balances[to] += value;
        balances[from] -= value;
        emit Transfer(from, to, value);
        return True;
    }        
        
    function approve(address spender, uint value) public returns(bool){
        allowance[msg.sender][spender] = value;
        emit Approval(msg.sender,spender,value);
        return true;
    }        
}