def change_nick(self,new_nick):
new_room_jid=JID(self.room_jid.node,self.room_jid.domain,new_nick)<EOL>p=Presence(to_jid=new_room_jid)<EOL>self.manager.stream.send(p)<EOL>
Send a nick change request to the room.

:Parameters:
    - `new_nick`: the new nickname requested.
:Types:
    - `new_nick`: `unicode`