Tkinter Listbox problems

I'm fairly new to Tkinter and GUI programming in Python (and Python in general, I'm trying to learn it...). The problem I am having right now is I am trying to have a functions set the selected item in a Tk.Listbox. The idea being a user can hit <up> or <down> and scroll up and down my listbox (from anywhere in the window, not just when the listbox has focus). I figured it would be the Listbox.select_set or Listbox.select_anchor methods, but neither seem to work. Below is a small snippet of my code:

filesListbox.select_set(1)
filesListbox.select_anchor(1)
filesListbox.select_includes(1)
print filesListbox.curselection()

the last line, the print, just prints an empty tuple... any ideas?

Thanks for the help
Matthew Bonig