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Bryan.sol

pragma solidity ^0.5.2;

contract Bryan{

    struct Data { mapping(uint => Fund) list; }
    
    struct Fund {
         address[] investorList;
    }
    
    Data data;

    function setValue() external {
        data.list[0].investorList.push(address(0xD6aE8250b8348C94847280928c79fb3b63cA453e));
       
    }
    
    function readValue() public returns (address) {
        return  data.list[0].investorList[0];
    }
}