二级的时候short CDS是买入CDS的意思，当时还专门强调跟平时理解的要反过来。
现在在三级里short CDS就是真的卖出CDS？完全反过来了吗
书上说：protection would be sold (i.e., shorting the CDS) on the target company to benefit from its improved credit quality (and decline in price of protection and the CDS) once a merger is completed。
