interface ICurveFi_4 {
    function get_virtual_price() external view returns (uint256);

    function add_liquidity(uint256[4] calldata amounts, uint256 min_mint_amount)
        external;

    // stETH pool
    function add_liquidity(
        uint256[2] calldata amounts,
        uint256 min_mint_amount
    ) external payable;

    function remove_liquidity_imbalance(
        uint256[4] calldata amounts,
        uint256 max_burn_amount
    ) external;

    function remove_liquidity(uint256 _amount, uint256[4] calldata amounts)
        external;

    function exchange(
        int128 from,
        int128 to,
        uint256 _from_amount,
        uint256 _min_to_amount
    ) external;

    function balances(int128) external view returns (uint256);
}
function add_liquidity(
    uint256[2] calldata amounts,
    uint256 min_mint_amount
) external payable;

// stETH pool