Guess the missing item from this list: α-3, α-7, α-4, α-5, β-0, α-9, β-2, β-1, α-0, α-8, β-5, β-3, β-6, α-1, α-6, α-2.
Directly answer with only one item. Item format should match the list format. Provide no explanation. Answer format: "{item}."