feat: add Price value object extending Money

domain/marketplace/price.py

@@ -0,0 +1,10 @@
+from dataclasses import dataclass
+
+from domain.marketplace.money import Money
+
+
+@dataclass(frozen=True)
+class Price(Money):
+    def __post_init__(self):
+        if self.amount < 0:
+            raise ValueError(f"Price cannot be negative: {self.amount}")