Function cw2::query_contract_info

pub fn query_contract_info<Q: Querier, T: Into<HumanAddr>>(
    querier: &Q, 
    contract_addr: T
) -> StdResult<ContractVersion>

This will make a raw_query to another contract to determine the current version it claims to be. This should not be trusted, but could be used as a quick filter if the other contract exists and claims to be a cw20-base contract for example. (Note: you usually want to require interfaces not implementations of the contracts you compose with, so be careful of overuse)