(command.CommandList
  children: [
    (command.If
      if_kw: <Id.KW_If if>
      arms: [
        (IfArm
          keyword: <Id.KW_If if>
          cond: 
            (condition.Shell
              commands: [
                (command.Sentence
                  child: 
                    (command.Simple
                      blame_tok: <Id.Lit_LBracket '['>
                      more_env: []
                      words: [
                        {<Id.Lit_LBracket '['>}
                        {(DQ ($ Id.VSub_DollarName SSH_CLIENT))}
                        {<Id.Lit_RBracket ']'>}
                      ]
                      redirects: []
                      do_fork: T
                    )
                  terminator: <Id.Op_Semi _>
                )
              ]
            )
          then_kw: <Id.KW_Then then>
          action: [
            (command.ShAssignment
              left: <Id.Lit_VarLike 'expression='>
              pairs: [
                (AssignPair
                  left: <Id.Lit_VarLike 'expression='>
                  lhs: (sh_lhs_expr.Name left:<Id.Lit_VarLike 'expression='> name:expression)
                  op: assign_op.Equal
                  rhs: 
                    {
                      (CommandSub
                        left_token: <Id.Left_DollarParen '$('>
                        child: 
                          (command.Pipeline
                            children: [
                              (command.Simple
                                blame_tok: <echo>
                                more_env: []
                                words: [{<echo>} {(DQ ($ Id.VSub_DollarName SSH_CLIENT))}]
                                redirects: []
                                do_fork: T
                              )
                              (command.Simple
                                blame_tok: <sed>
                                more_env: []
                                words: [
                                  {<sed>}
                                  {
                                    (SQ <'s/.*://;\n'> 
                                      <
'         s/^\\([0-9.]*\\) [0-9]* \\([0-9]*\\)$/not \\( host \\1 and port \\2 \\)/'
                                      >
                                    )
                                  }
                                ]
                                redirects: []
                                do_fork: T
                              )
                            ]
                            ops: [<Id.Op_Pipe _>]
                          )
                        right: <Id.Eof_RParen _>
                      )
                    }
                )
              ]
              redirects: []
            )
          ]
          spids: [45 56]
        )
      ]
      else_action: []
      fi_kw: <Id.KW_Fi fi>
      redirects: []
    )
    (command.Simple
      blame_tok: <tcpdump>
      more_env: []
      words: [{<tcpdump>} {(DQ ($ Id.VSub_At '@'))} {($ Id.VSub_DollarName expression)}]
      redirects: []
      do_fork: T
    )
  ]
)