CodeSizeTest: The code size of an address greater than zero bytes is a contract. Does it mean the code size of an address equal zero bytes is a EOA? (Write a PoC to validate it)

DaoTokenTest: test how hacker can get votes and tokens if he has users' private keys.

FrontRun: What is the potential risk of directly overwriting the old value of _allowance? (Write a PoC to validate it)