How to verify source code of old contract(ERC20)? [SOLVED]

Support
1

Quite some time ago i've launched a token(ERC20 from openzeppelin), i thought i verified the smart contract, but it seems like i have not :expressionless: :cold_sweat:

It was a classical ERC20 from openzeppelin with fixed supply. I know the supply, i know the name and ticker and the address that launched the contract.

But i forgot the exact code that was used for launching the contract, contract name and the solidity version.
I've already attempted a several times but was unable to verify it.
Any suggestions? Much appreciated, thanks!

I think this is the code i used, or atleast a similar. If i try to compile the contract with Solidity 0.6.0, it says openzeppelin ERC20 requires atleast 0.8.0 ... How can i go back in time and get source for ERC20 with solidity 0.6.0?

// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";

contract ERC20FixedSupply is ERC20 {
    constructor() public ERC20("Name", "Ticker") {
        _mint(msg.sender, 100000000000);
    }
}

:pray: :pray: :pray:

2

This line of code only imports the latest version, and if you are certain about the version of contract you used, you can go to the historical version of OZ contracts and manually copy and paste it into this contract.

3

Thanks, i managed to do it.

What i ended up doing:
1.) Checked when the contract was launched on etherscan
2.) Found version of openzeppelin contracts that were in use at the time of launch

3.) When importing, instead of /contracts/ folder use /contracts@x.x.x/ where x.x.x is the openzeppelin release at the time
4.) I didn't remember the compiler version i used so i had to try it a few times
5.) Compile the contract in remix(try different compiler versions if needed), flatten the token and verify it on etherscan

4

How can I contact you please?

6

How can I know the Openzeppelin version used in the contract:: Package.json file?

I can't see @openzeppelin/contracts vX used.