type t = {mutable request_id : Dtcprotocol_piqi.protobuf_int32 option;mutable total_number_messages : Dtcprotocol_piqi.protobuf_int32 option;mutable message_number : Dtcprotocol_piqi.protobuf_int32 option;mutable symbol : string option;mutable exchange : string option;mutable quantity : Dtcprotocol_piqi.float64 option;mutable average_price : Dtcprotocol_piqi.float64 option;mutable position_identifier : string option;mutable trade_account : string option;mutable no_positions : bool option;mutable unsolicited : bool option;mutable margin_requirement : Dtcprotocol_piqi.float64 option;mutable entry_date_time : Dtcprotocol_piqi.uint32 option;}