choice      :native_os,      label: 'Native OS', selection: -> { parent.smb_header.flags2.unicode } do
            stringz   0, initial_value: 'Windows 7 Ultimate N 7601 Service Pack 1'
            stringz16 1, initial_value: 'Windows 7 Ultimate N 7601 Service Pack 1'.encode('utf-16le')
          end