Hi. I am wondering about some holes on the inside of my sweet potatoes. To be honest, these are not sweet potatoes that I grew, but are from the farmers' market. When I baked them and opened them, I noticed these openings, and I don't know if they are from pests, or if maybe it has to do with something like moisture conditions as the plants were growing. I also cut open a couple of them prior to baking and they had similar patterns. Can anyone tell me what this is? Thank you in advance!

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