(command.CommandList
  children: [
    (command.ShAssignment
      pairs: [
        (assign_pair
          lhs: (sh_lhs_expr.Name name:disk)
          op: assign_op.Equal
          rhs: {(DQ <kube-master-disk.img>)}
          spids: [3]
        )
      ]
    )
    (C {<set>} {<-x>})
    (C {<rm>} {<-f>} {(DQ (${ Id.VSub_Name disk))})
    (C {<'../../bin/moby'>} {<run>} {<hyperkit>} {<-cpus>} {<2>} {<-mem>} {<4096>} {<-disk-size>} {<4096>} 
      {<kube-master>}
    )
  ]
)