feat: add max 2 decimal places validation to Money

tests/test_money.py

@@ -37,3 +37,26 @@ def test_money_substract():
     money1 = Money(amount=Decimal("5.00"))
     money2 = Money(amount=Decimal("3.00"))
     assert (money1 - money2) == Money(amount=Decimal("2.00"))
+
+
+def test_money_can_not_have_more_than_two_decimals():
+    try:
+        Money(amount=Decimal("1.234"))
+        assert False, "Should have raised ValueError"
+    except ValueError:
+        pass
+
+
+def test_money_allows_two_decimals():
+    money = Money(amount=Decimal("1.23"))
+    assert money.amount == Decimal("1.23")
+
+
+def test_money_allows_one_decimal():
+    money = Money(amount=Decimal("1.2"))
+    assert money.amount == Decimal("1.2")
+
+
+def test_money_allows_no_decimals():
+    money = Money(amount=Decimal(1))
+    assert money.amount == Decimal(1)