feat(*): Add pumpkins

pumpkins.py

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+import helpers
+
+# Pumpkins grow like carrots on tilled soil. Planting them costs carrots.
+
+# When all the pumpkins in a square are fully grown, they will grow together to form a giant pumpkin. Unfortunately, pumpkins have a 20% chance of dying once they are fully grown, so you will need to replant the dead ones if you want them to merge. 
+
+# When a pumpkin dies, it leaves behind a dead pumpkin that won't drop anything when harvested. Planting a new plant in its place automatically removes the dead pumpkin, so there is no need to harvest it. can_harvest() always returns False on dead pumpkins.
+
+# The yield of a giant pumpkin depends on the size of the pumpkin.
+
+# A 1x1 pumpkin yields 1*1*1 = 1 pumpkins.
+# A 2x2 pumpkin yields 2*2*2 = 8 pumpkins instead of 4.
+# A 3x3 pumpkin yields 3*3*3 = 27 pumpkins instead of 9.
+# A 4x4 pumpkin yields 4*4*4 = 64 pumpkins instead of 16.
+# A 5x5 pumpkin yields 5*5*5 = 125 pumpkins instead of 25.
+# A nxn pumpkin yields n*n*6 pumpkins for n >= 6.
+
+# It's a good idea to get at least 6x6 size pumpkins to get the full multiplier. 
+
+# This means that even if you plant a pumpkin on every tile in a square, one of the pumpkins may die and prevent the mega pumpkin from growing.
+
+def till_and_plant():
+    if get_ground_type() != Grounds.Soil:
+        till()
+    if get_entity_type() == Entities.Pumpkin:
+        helpers.harvest_if_possible()
+        plant(Entities.Pumpkin)
+    else:
+        helpers.harvest_if_possible()
+        plant(Entities.Pumpkin)
+
+def clear_bad_pumpkins():
+    for x in range(get_world_size()):
+        for y in range(get_world_size()):
+            if get_entity_type() == Entities.Dead_Pumpkin:
+                # Planting a new plant in its place automatically removes the dead pumpkin, so there is no need to harvest it. 
+                plant(Entities.Pumpkin)
+            move(North)
+        move(East)
+        
+def harvest_pumpkins():
+    for x in range(get_world_size()):
+        for y in range(get_world_size()):
+            till_and_plant()
+            move(North)
+        move(East)
+
+    for i in range(5):
+        # 5 because the decay rate is 20% so 5 passes should usually clear all bad pumpkinks to maximise harvest
+        clear_bad_pumpkins()