Facing some errors while following exact steps of https://forum.openzeppelin.com/t/verifying-a-contract-inheriting-from-openzeppelin-contracts/1119. I am trying to verify my deployed code using @openzeppelin/contracts.
I tried 1. truffle-flattener, 2. manually adding all files using multi-part files.
but it gives the same error again and again.
it says:
