oop - how python manage object delete or destruction -

guys, rather new python , learning build gui application (with wypython). have question related object destruction in python. e.g. in myframe have onnew (create new document) , onopen (open file) method.

briefly, looks this.

def onnew     self.data=datamodel()     self.viewwindow=viewwindow(self.data)   def onopen     dlg = wx.filedialog(self, "open file", os.getcwd(), "", "*.*", wx.open)         if dlg.showmodal() == wx.id_ok:             self.data=datamodel.from_file(...)             self.view=view(self.data) 

now, want consider "if user click open or new again, after click either before."

so window classes, call self.viewwindow.destroy() destry windows. data model object? if first call new: self.data=datamodel(), call open , re-assign self.data=datamodel.from_file(...), old instance? need destruct myself or python manage destruction?

python has garbage collection. long don't have references old object hanging around collected.

as self.data = somethingelse old self.data won't have references (unless object had reference object's self.data).