first hack at a version for each language, translated from the C#.

GildedRose/python/gilded_rose.py

@@ -0,0 +1,48 @@
+
+def update_quality(items):
+    for item in items:
+        if item.name != "Aged Brie" and item.name != "Backstage passes to a TAFKAL80ETC concert":
+            if item.quality > 0:
+                if item.name != "Sulfuras, Hand of Ragnaros":
+                    item.quality = item.quality - 1;
+        else:
+            if item.quality < 50:
+                item.quality = item.quality + 1;
+                if item.name == "Backstage passes to a TAFKAL80ETC concert":
+                    if item.sell_in < 11:
+                        if item.quality < 50:
+                            item.quality = item.quality + 1;
+                    if item.sell_in < 6:
+                        if item.quality < 50:
+                            item.quality = item.quality + 1;
+        if item.name != "Sulfuras, Hand of Ragnaros":
+            item.sell_in = item.sell_in - 1;
+        if item.sell_in < 0:
+            if item.name != "Aged Brie":
+                if item.name != "Backstage passes to a TAFKAL80ETC concert":
+                    if item.quality > 0:
+                        if item.name != "Sulfuras, Hand of Ragnaros":
+                            item.quality = item.quality - 1;
+                else:
+                    item.quality = item.quality - item.quality;
+            else:
+                if item.quality < 50:
+                    item.quality = item.quality + 1;
+    return items
+
+class Item:
+    def __init__(self, name, sell_in, quality):
+        self.name = name
+        self.sell_in = sell_in
+        self.quality = quality
+        
+if __name__ == "__main__":
+    items = [
+             Item(name="+5 Dexterity Vest", sell_in=10, quality=20),
+             Item(name="Aged Brie", sell_in=2, quality=0),
+             Item(name="Elixir of the Mongoose", sell_in=5, quality=7),
+             Item(name="Sulfuras, Hand of Ragnaros", sell_in=0, quality=80),
+             Item(name="Backstage passes to a TAFKAL80ETC concert", sell_in=15, quality=20),
+             Item(name="Conjured Mana Cake", sell_in=3, quality=6),
+            ]
+    update_quality(items)

GildedRose/python/test_gilded_rose.py

@@ -0,0 +1,6 @@
+from gilded_rose import Item, update_quality
+
+def test_foo():
+    items = [Item("foo", 0, 0)]
+    update_quality(items)
+    assert "fixme" == items[0].name