returns smallest integer not less than the distance of two points

def distCEIL2D(x1,y1,x2,y2):
    """returns smallest integer not less than the distance of two points"""
    xdiff = x2 - x1
    ydiff = y2 - y1
    return int(math.ceil(math.sqrt(xdiff*xdiff + ydiff*ydiff)))