The snake wine is actually the blood of the snake. 
Is an alcoholic a berage produced by infusing whole snakes in rice wine or grain acohol! The drink was first recorded to have been consumed in China during the Western Zhou dynasty and considered an important curative and believed to reivigorate a person according to a traditional chinese medicine. It can be found in China, Vietnam and throughout Southeast Asia.

                          As you can see in this video how is the process to sold the snake wine.

VARIETIES

Are two kinds of snake wine:

• STEEPED: A large venemous can be placed into a glass jar of rice wine, sometimes with smaller snakes and medicinal herbs and left to steep for many months the wine is drunk ass a restorative in smaller shots or cups.

MIXED:Body fluids of snake are mixed into wine and consumed immediately in the form of a shot. Snake blood wine is prepared by slicing a snake along its belly and draining its blood directly into the drinking vessel filled with rice wine or grain alcohol. Snake bile wine is done through a similar method by using the contents of the gall bladder.   

•  On the video you can see how the people prepares the snake wine.