Is there a chorus in this? How are the classical chorus functions treated?

Yes there is a chorus in the play. The chorus introduces the play and establishes the plot that will unfold. The chorus relates the action to the audience and sometimes foreshadows details. The chorus, to some extent, removes suspense from the play. Shakespeare, however, wants us to consider the characters rather than the outcome. Unlike the classic chorus in Greek tragedies, this chorus does not interact with the characters in the play.