Congratulations on your new puppy!!!
For starters I would make an appt to see a vet to check and make sure the dog is healthy. And while there they can verify the sex of the dog for you.
My opinion, it looks like a boy to me. That's what my boy looked like at 7 wks, I couldn't tell him between a boy or a girl. After a few months his testes started to show and drop, so then I really knew he was a boy. I think your safe to say he's a boy, but if you want an "expert" opinion see a vet
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