minor fixes

pypretix_device/models.py

@@ -43,6 +43,15 @@ class Event:
     date_to: Optional[str] = None
 
 
+@dataclass
+class Item:
+    """A product/item within an event."""
+
+    id: int
+    name: str
+    internal_name: Optional[str] = None
+
+
 @dataclass
 class CheckinList:
     """A check-in list within an event."""