This is an unusual structure, but it's grammatically correct since it has a list within a list, and the items in both lists are parallel.
For example, I can say "The recent flood has not only damaged crops and forced the government to ask for international aid, but also severely affected the country's economy." In this sentence, "damaged" and "affected" are parallel elements joined by "not only" and "but also". There is also a list within a list, since "damaged" and "forced" also form of a parallel list.
It's perfectly okay to have a list within a list as long as the main list and the nested list both have parallel items.
I hope this helps!
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