In a large patch of dirt in my backyard (where a tree used to prevent grass from growing), my Punkin' Chunkin' teammates decided to test-grow some pumpkin seeds from left over pumpkins for last years chunk. There should be lots of various pumpkins growing together back there, and I found this plant. I think it's a weed, my teammates think it's just an unusual pumpkin. Can you identify this? If it's a weed, I want to gloat then remove it.

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