(CommandList
  children: [
    (Assignment
      keyword: Assign_None
      pairs: [
        (assign_pair
          lhs: (LhsName name:KUBE_ROOT)
          op: Equal
          rhs: 
            {
              (CommandSubPart
                command_list: 
                  (CommandList
                    children: [(C {(dirname)} {(DQ (${ VSub_Name BASH_SOURCE))})]
                  )
                left_token: <Left_CommandSub '$('>
                spids: [48 56]
              ) (/../..)
            }
          spids: [47]
        )
      ]
      spids: [47]
    )
    (C {(source)} {(DQ (${ VSub_Name KUBE_ROOT) (/cluster/centos/config-default.sh))})
  ]
)