Ownable.sol

pragma solidity ^0.4.21;

contract OwnableData {
    modifier onlyOwner() {
        require(msg.sender == owner);
        _;
    }

    address internal owner;

    function OwnableData(address _owner)
        public
    {
        owner = _owner;
    }
}

contract Ownable is OwnableData {
    function setOwner(address newOwner)
        public
        onlyOwner
    {
        owner = newOwner;
    }
}