[Tutor] curses

[max baseman]

ok after reading a few tutorials i think i know enough to write my  
program
here it  is
not commented yet though sorry:

import curses
from time import sleep
scr=vurses.initscr()
population=0
seconds=0
try:
	scr.nodelay(1)
	scr.leaveok(0)
	max_y, max_x = scr.getmaxyx()
	while scr.getch()== -1:
	sleep(1)
	seconds=seconds+1
	population=population+2.5
	scr.addstr(0,0,"seconds:",seconds")  # i would like to get this  
bottom left but didn't know how
	scr.sddch(1,0,population) # here is ware i think I'm having problems  
also would like this to be centered
	scr.clear()
	scr.refresh()
finaly:
	curses.endwin()




but i get the error:

traceback (most recent call last):
  file "population.py", line 15, in <module>
	scr.addch(1,0,population)
TypeError: argument 1 or 3 must be a ch or an int



thank you