Got some tests working

tests/factories.py

@@ -0,0 +1,31 @@
+import factory
+
+from random import choice
+
+from tests.market.models import Item, Shop, Inventory
+
+
+class ItemFactory(factory.django.DjangoModelFactory):
+    class Meta:
+        model = Item
+
+    name = factory.Faker('name')
+    price = factory.Faker('price')
+    currency = factory.LazyAttribute(lambda _: choice(Item.VALID_CURRENCIES))
+
+
+class ShopFactory(factory.django.DjangoModelFactory):
+    class Meta:
+        model = Shop
+
+    name = factory.Faker('name')
+
+
+class InventoryFactory(factory.django.DjangoModelFactory):
+    class Meta:
+        model = Inventory
+
+    shop = factory.SubFactory(ShopFactory)
+    item = factory.SubFactory(ItemFactory)
+    quantity = factory.Sequence(lambda n: n)
+