Function read_cds 

pub(crate) fn read_cds<'a, 'd>(
    trade: El<'_, '_>,
    cds: El<'a, 'd>,
    trade_date: NaiveDate,
    ctx: &Context<'_>,
) -> Result<Read<'a, 'd>, FpmlError>

Reads a creditDefaultSwap: the contract, its initial payment a fee.