contract WithAdmin {
    address internal _admin;

    /// @dev Emits when the contract administrator is changed.
    /// @param oldAdmin The address of the previous administrator.
    /// @param newAdmin The address of the new administrator.
    event AdminChanged(address oldAdmin, address newAdmin);

    modifier onlyAdmin() {
        require(msg.sender == _admin, "ADMIN_ONLY");
        _;
    }

    /// @dev Get the current administrator of this contract.
    /// @return The current administrator of this contract.
    function getAdmin() external view returns (address) {
        return _admin;
    }

    /// @dev Change the administrator to be `newAdmin`.
    /// @param newAdmin The address of the new administrator.
    function changeAdmin(address newAdmin) external {
        require(msg.sender == _admin, "ADMIN_ACCESS_DENIED");
        emit AdminChanged(_admin, newAdmin);
        _admin = newAdmin;
    }
}
function getAdmin() external view returns (address) {
    return _admin;
}

/// @dev Get the current administrator of this contract.
/// @return The current administrator of this contract.