Unless you manually specify the colors, curses is going to respect your terminals color palette. Most terminals will use your settings from a .Xresources or .Xdefaults file (not sure about gnome-terminal)
However if you want to manually define your colors. Use curses.init_color, this doesn't work on all terminals, more info on its usage in the python curses documentation. Do remember to reset the colors before quitting (curses.wrapper should do this for you).
def func(stdscr):
if curses.can_change_color():
# init_color(n, r, g, b)
# n=0 is background
curses.init_color(0, 0, 0, 0)
c = stdscr.getkey()