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FactoryTest.sol

pragma solidity ^0.5.0;

contract Child {
    
    address creator;
    event newChild(address _a);
    
    constructor()
        public
    {
        creator = msg.sender; 
        emit newChild(msg.sender);
    }
    
}

contract Factory {
    
    event log(address _b);
    
    function newChild()
        public
    {
        Child c = new Child();
        emit log(msg.sender);
    }
    
}