Who is "you" in Genesis 3:15 according to the Calvinist? I have a "connected" question before in here. And I think I made a mistake to ask a question like that directly.

So, I will start here first :


  Genesis 3:15 I will put enmity between you and the woman, and between
  your offspring and her offspring; he shall bruise your head, and you
  shall bruise his heel.


Who is "you" there ? Who did God talk to ? was God addressing reptile?
It was Satan


  ”I acknowledge, indeed, that from this place alone nothing more can be collected than that men were deceived by the serpent. But the testimonies of Scripture are sufficiently numerous, in which it is plainly asserted that the serpent was only the mouth of the devil; for not the serpent but the devil is   declared to be the father of lies,' the fabricator of imposture, and   the author of death. The question, however, is not yet solved, why   Moses has kept back the name of Satan. I willingly subscribe to the   opinion of those who maintain that the Holy Spirit then purposely used   obscure figures, because it was fitting that full and clear light   should be reserved for the kingdom of Christ. In the meantime, the   prophets prove that they were well acquainted with the meaning of Moses, when, in different places, they cast the blame of our ruin upon  the devil. (Calvin, John. The Complete Biblical Commentary Collection of John Calvin. Kindle location 2840)”.  


This view is consistent among Calvinists.