Complete twelve-days: implement recite with tuples, add exemplar.py a…

exercises/practice/twelve-days/.meta/example.py

@@ -1,29 +1,28 @@
-GIFTS = ['twelve Drummers Drumming',
-         'eleven Pipers Piping',
-         'ten Lords-a-Leaping',
-         'nine Ladies Dancing',
-         'eight Maids-a-Milking',
-         'seven Swans-a-Swimming',
-         'six Geese-a-Laying',
-         'five Gold Rings',
-         'four Calling Birds',
-         'three French Hens',
-         'two Turtle Doves',
-         'a Partridge in a Pear Tree']
-
-ORDINAL = [None, 'first', 'second', 'third', 'fourth', 'fifth', 'sixth',
-           'seventh', 'eighth', 'ninth', 'tenth', 'eleventh', 'twelfth']
-
-
-def verse(day_number):
-    gifts = GIFTS[-day_number:]
-
-    if len(gifts) > 1:
-        gifts[:-1] = [', '.join(gifts[:-1])]
-
-    gifts = ', and '.join(gifts)
-    return f'On the {ORDINAL[day_number]} day of Christmas my true love gave to me: {gifts}.'
-
-
-def recite(start, end):
-    return [verse(number) for number in range(start, end + 1)]
+def recite(start_verse, end_verse):
+    gifts = (
+        "a Partridge in a Pear Tree",
+        "two Turtle Doves",
+        "three French Hens",
+        "four Calling Birds",
+        "five Gold Rings",
+        "six Geese-a-Laying",
+        "seven Swans-a-Swimming",
+        "eight Maids-a-Milking",
+        "nine Ladies Dancing",
+        "ten Lords-a-Leaping",
+        "eleven Pipers Piping",
+        "twelve Drummers Drumming"
+    )
+    ordinals = (
+        "first", "second", "third", "fourth", "fifth", "sixth",
+        "seventh", "eighth", "ninth", "tenth", "eleventh", "twelfth"
+    )
+
+    def build_verse(n):
+        day = n - 1
+        verse = f"On the {ordinals[day]} day of Christmas my true love gave to me: "
+        verse_gifts = [f"and {gifts[0]}" if i == 0 and day > 0 else gifts[i] for i in range(day, -1, -1)]
+        verse += ", ".join(verse_gifts) + "."
+        return verse
+
+    return [build_verse(n) for n in range(start_verse, end_verse + 1)]

exercises/practice/twelve-days/.meta/exemplar.py

@@ -0,0 +1,28 @@
+def recite(start_verse, end_verse):
+    gifts = (
+        "a Partridge in a Pear Tree",
+        "two Turtle Doves",
+        "three French Hens",
+        "four Calling Birds",
+        "five Gold Rings",
+        "six Geese-a-Laying",
+        "seven Swans-a-Swimming",
+        "eight Maids-a-Milking",
+        "nine Ladies Dancing",
+        "ten Lords-a-Leaping",
+        "eleven Pipers Piping",
+        "twelve Drummers Drumming"
+    )
+    ordinals = (
+        "first", "second", "third", "fourth", "fifth", "sixth",
+        "seventh", "eighth", "ninth", "tenth", "eleventh", "twelfth"
+    )
+
+    def build_verse(n):
+        day = n - 1
+        verse = f"On the {ordinals[day]} day of Christmas my true love gave to me: "
+        verse_gifts = [f"and {gifts[0]}" if i == 0 and day > 0 else gifts[i] for i in range(day, -1, -1)]
+        verse += ", ".join(verse_gifts) + "."
+        return verse
+
+    return [build_verse(n) for n in range(start_verse, end_verse + 1)]

exercises/practice/twelve-days/read.md

@@ -0,0 +1,9 @@
+# Twelve Days
+
+Output the lyrics to 'The Twelve Days of Christmas'.
+
+```text
+On the first day of Christmas my true love gave to me: a Partridge in a Pear Tree.
+
+On the second day of Christmas my true love gave to me: two Turtle Doves, and a Partridge in a Pear Tree.
+...

exercises/practice/twelve-days/twelve_days.py

@@ -1,2 +1,28 @@
 def recite(start_verse, end_verse):
-    pass
+    gifts = (
+        "a Partridge in a Pear Tree",
+        "two Turtle Doves",
+        "three French Hens",
+        "four Calling Birds",
+        "five Gold Rings",
+        "six Geese-a-Laying",
+        "seven Swans-a-Swimming",
+        "eight Maids-a-Milking",
+        "nine Ladies Dancing",
+        "ten Lords-a-Leaping",
+        "eleven Pipers Piping",
+        "twelve Drummers Drumming"
+    )
+    ordinals = (
+        "first", "second", "third", "fourth", "fifth", "sixth",
+        "seventh", "eighth", "ninth", "tenth", "eleventh", "twelfth"
+    )
+
+    def build_verse(n):
+        day = n - 1
+        verse = f"On the {ordinals[day]} day of Christmas my true love gave to me: "
+        verse_gifts = [f"and {gifts[0]}" if i == 0 and day > 0 else gifts[i] for i in range(day, -1, -1)]
+        verse += ", ".join(verse_gifts) + "."
+        return verse
+
+    return [build_verse(n) for n in range(start_verse, end_verse + 1)]