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contracts...immutable.sol

//SPDX-License-Identifier: MIT

pragma solidity ^0.8;


contract Immutable{

    //immutable state variable can be set inline - constructor
    address public immutable owner;
    //constant defined only inline
    address public constant owner2 =  address(1);
    //simple state variable defined.
    address public owner3 = address(2);

    constructor(address _owner){
        owner = _owner;
    }

    function IO() public view returns(address){
        return owner;
    }

    function CO() public pure returns(address){
        return owner2;
    }
    
    function PO() public view returns(address){
        return owner3;
    }




}