Workaround Pylint bug.

Author: kattni

adafruit_led_animation/animation/comet.py

@@ -68,12 +68,12 @@ def __init__(
         pixel_object,
         speed,
         color,
-        tail_length=None,
+        tail_length=0,
         reverse=False,
         bounce=False,
         name=None,
     ):
-        if tail_length is None:
+        if tail_length is 0:
             tail_length = len(pixel_object) // 4
         else:
             tail_length = max(2, min(tail_length, len(pixel_object)))