`object
method charset : string
method content_type : string
method content_type_params : (string * Mimestring.s_param) list
method filename : string option
method finalize : unit -> unit
method name : string
method open_value_rd : unit -> Netchannels.in_obj_channel
method open_value_wr : unit -> Netchannels.out_obj_channel
method representation : Netcgi_types.representation
method ro : bool
method set_value : string -> unit
method store : Netcgi_types.store
method value : string
end`