Function fetch_abi_from_etherscan 

pub async fn fetch_abi_from_etherscan(
    address: Address,
    config: &Config,
    follow_proxy: bool,
) -> Result<Vec<(JsonAbi, String)>>

Fetches the ABI of a contract from Etherscan.

If follow_proxy is set and Etherscan reports the contract as a proxy, the ABI of its implementation is appended after the proxy’s own. Failing to fetch the implementation only produces a warning.