Create a more advanced version of the light sensor -> circle of LEDs program

Introducing_CircuitPlaygroundExpress/CircuitPlaygroundExpress_LightSensor_Four_Colors.py

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+"""Maps light level to multiple circles of colors.
+
+The light intensity level is divided into four bands.
+Dim light creates a growing circle of blue lights,
+followed by circles of green, yellow, and then red lights
+for the highest intensity."""
+
+import time
+import board
+import neopixel
+from analogio import AnalogIn
+
+NUM_LEDS = 10
+
+pixels = neopixel.NeoPixel(board.NEOPIXEL, NUM_LEDS, auto_write=0, brightness=.3)
+pixels.fill((0, 0, 0))
+pixels.show()
+
+sensor = AnalogIn(board.LIGHT)
+hues = (
+    (  0,   0, 255),  # Blue
+    (  0, 255,   0),  # Green
+    (255, 255,   0),  # Yellow
+    (255,   0,   0),  # Red
+)
+
+while True:
+    normalized_brightness = sensor.value / 65535
+    hues_position = normalized_brightness * len(hues)
+    hue_idx = int(hues_position)
+    hue_fill_fraction = hues_position - hue_idx
+
+    pixels.fill((0, 0, 0))
+
+    for led_idx in range(int(hue_fill_fraction * NUM_LEDS) + 1):
+        pixels[9 - led_idx] = hues[hue_idx]
+
+    pixels.show()
+
+    time.sleep(0.01)