On version 4.1.0
color values passed as tuples (r,g,b) are returned as `[brightnessr,brightnessb,brightness*c]
import board
import neopixel
color_red=(80,0,0)
self.pixels = neopixel.NeoPixel(board.D18, 256, auto_write=False, brightness=0.5)
red = (80,0,0)
pixels[1] = red
print( pixels[1])
Prints [40,0,0]