[
{
    "constant": true,
    "inputs": [
        {
            "name": "a",
            "type": "string"
        }
    ],
    "name": "check",
    "outputs": [
        {
            "name": "",
            "type": "string"
        }
    ],
    "payable": false,
    "stateMutability": "pure",
    "type": "function"
}
]

contract Test {
  function check(string a) public pure returns(string);
}