Based on Gake no Ue no Ponyo (Ponyo on the Cliff), the boat used by Ponyo's father Fujimoto, it's a boat and a sub at the same time.
To download the template, follow the link below, scroll to the bottom of the page (you'll see a photo of the boat) and click on the star symbol on the right side of the photo.
Ponyo Papercraft - Fujmoto's Boat (Submarine) [Download]
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