How to define a lock function in a smart contract?

Question

blockchain

Now many people have begun to raise the issue of blocking cryptocurrencies (tokens) such as USDT USDC and so on. I want to check the information in which tokens do not have the function of locking (locking) tokens by calling a specific function in a smart contract.

Tell me how to define a function in a smart contract that allows you to determine the possibility of blocking, what does it look like?

Answer 1

I found an answer for those who are interested in the USDT example.

The function is usually called freeze frozen blacklist, if you briefly look in the Write Contract tab, look at the functions further in the contract code, look for a function and what it does