pybricks.parameters: Add/fix operators for Color type.

* Implement `Color.__eq__`, fix `Color.__mul__`. This allows testing of color block sorting algorithms with CPython.
* implement `Color.__lshift__` and immutability for completeness.

Author: kai-morich

src/pybricks/parameters.py

@@ -112,18 +112,26 @@ def __init__(self, h: Number, s: Number = 100, v: Number = 100):
         The brightness value.
         """
 
+    def __setattr__(self, key, value):
+        if key not in ("h", "s", "v"):
+            raise AttributeError("Can't modify unknown attribute: " + key)
+        if hasattr(self, key):  # immutable after __init__
+            raise AttributeError("Can't modify immutable attribute: " + key)
+        super().__setattr__(key, value)
+
     def __iter__(self):
         """Allows unpacking of the Color instance into h, s, and v."""
         return iter((self.h, self.s, self.v))
 
     def __repr__(self):
         return "Color(h={}, s={}, v={})".format(self.h, self.s, self.v)
 
-    def __eq__(self, other: Color) -> bool: ...
+    def __eq__(self, other: Color) -> bool:
+        return self.h == other.h and self.s == other.s and self.v == other.v
 
     def __mul__(self, scale: float) -> Color:
         v = max(0, min(self.v * scale, 100))
-        return Color(self.h, self.s, int(v), self.name)
+        return Color(self.h, self.s, int(v))
 
     def __rmul__(self, scale: float) -> Color:
         return self.__mul__(scale)
@@ -134,6 +142,12 @@ 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)