Can some one please tell me what this is

I presume it is a squash duh ! but what kind of Squash

It grew out of my Manure/Compost pile Horse Manure and

Cow manure compost The only squash to hit the pile was a Acorn Squash that came up last year by it self by the Giant Pumpkin patch and this year this came up from the

compost/manure pile could this be a cross from last years pumpkin and a Acorn squash ?

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