(command.CommandList
  children: [
    (C {<'/usr/bin/echo'>})
    (C {<'/usr/bin/date'>})
    (command.Pipeline
      children: [
        (C {<'/usr/bin/cat'>} {<-sv>} 
          {
            (command_sub
              left_token: <Id.Left_Backtick '`'>
              child: 
                (command.Simple
                  words: [{<'/usr/bin/ls'>} {<-tr1>} {<'/var/adm/messages.'> <Id.Lit_QMark '?'>}]
                  redirects: [
                    (redir
                      op: <Id.Redir_Great '2>'>
                      loc: (redir_loc.Fd fd:2)
                      arg: {<'/dev/null'>}
                    )
                  ]
                  more_env: []
                  do_fork: T
                )
              right: <Id.Backtick_Right '`'>
            )
          } {<'/var/adm/messages'>}
        )
        (C {<'/usr/bin/tail'>} {<-200>})
      ]
      negated: F
      stderr_indices: []
    )
  ]
)