LinkTokenOnMatic.sol

pragma solidity ^0.6.0;


import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v3.2.0/contracts/token/ERC20/IERC20.sol";

contract LinkTokenOnMatic {
    
    IERC20 public token;
    
    // child chain manager
    address public depositor;
    address public deployer;
    
    // This is the address of deployed & unchanged v4 LinkToken
    constructor(address _token) public {
        token = IERC20(_token);
        require(token.totalSupply() == token.balanceOf(address(this)), "I need to have it all.");
        // child chain manager proxy
        depositor =  0xb5505a6d998549090530911180f38aC5130101c6;
        deployer =  msg.sender;
    }
    
    function updateDepositor(address newDespositor) external {
        require(msg.sender == deployer, "You can't update me");
        depositor = newDespositor;
    }
    
    
    // additional methods needed for enabling cross chain asset transfer
    
    function deposit(address user, bytes calldata depositData) external {
        require(msg.sender == depositor, "Only ChildChainManager can deposit");
        require(user != address(0), "Not a valid address");
        
        uint256 amount = abi.decode(depositData, (uint256));
        token.transfer(user, amount);
    }
    
    function withdraw(uint256 amount) external {
        token.transferFrom(msg.sender, address(this), amount);
    }
}

Alright 👍