Adafruit CircuitPython 9.0.0 on 2024-03-19; Adafruit ItsyBitsy ESP32 with ESP32

# import time
# import board
# import neopixel

# pixels = neopixel.NeoPixel(board.NEOPIXEL, 1)

# while True:
#     pixels.fill(0xADAF00)
#     time.sleep(1)
#     pixels.fill(0)
#     time.sleep(1)

import board
import digitalio
import neopixel
import time

print("START")
# On MagTag, enable power to NeoPixels.
# Remove these two lines on boards without board.NEOPIXEL_POWER.
# np_power = digitalio.DigitalInOut(board.NEOPIXEL_POWER)
# np_power.switch_to_output(value=False)

np = neopixel.NeoPixel(board.NEOPIXEL, 1)

np[0] = (50, 50, 50)
time.sleep(1)
np[0] = (0, 0, 0)

soft reboot

Auto-reload is on. Simply save files over USB to run them or enter REPL to disable.
code.py output:
START
Traceback (most recent call last):
  File "code.py", line 24, in <module>
  File "/lib/neopixel.py", line 141, in __init__
ValueError: NEOPIXEL in use

Code done running.

Press any key to enter the REPL. Use CTRL-D to reload.