implement Color.__lshift__ and immutability

Author: kai-morich

src/pybricks/parameters.py

@@ -112,6 +112,12 @@ def __init__(self, h: Number, s: Number = 100, v: Number = 100):
         The brightness value.
         """
 
+    def __setattr__(self, key, value):
+            if not hasattr(self, key):
+                super().__setattr__(key, value)
+            else: # immutable after __init__
+                raise AttributeError("Can't modify immutable object attribute: " + key)
+
     def __iter__(self):
         """Allows unpacking of the Color instance into h, s, and v."""
         return iter((self.h, self.s, self.v))
@@ -135,6 +141,11 @@ def __truediv__(self, scale: float) -> Color:
     def __floordiv__(self, scale: int) -> Color:
         return self.__mul__(1 / scale)
 
+    def __lshift__(self, shift: int) -> Color:
+        return self.__rshift__(-shift)
+
+    def __rshift__(self, shift: int) -> Color:
+        return Color((self.h + shift) % 360, self.s, self.v)
 
 Color.NONE = Color(0, 0, 0)
 Color.BLACK = Color(0, 0, 10)