You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: general.rs
    path of file: ./repos/SquireCore/squire_lib/src/settings
    
    the code of the file until where you have to start completion: use std::time::Duration;

use serde::{Deserialize, Serialize};

use super::SettingsTree;
use crate::{
    error::TournamentError,
    operations::{OpData, OpResult},
};

/// An enum that encode all of the general tournament settings
#[der
    
    fn iter(&self) -> Box<dyn Iterator<Item = Self::Setting>> {
        Box::new(
            [
                GeneralSetting::Format(self.format.clone()),
                GeneralSetting::StartingTableNumber(self.starting_table_number),
                GeneralSetting::UseTableNumbers(self.use_table_number),
                GeneralSetting::MinDeckCount(self.min_deck_count),
                GeneralSetting::MaxDeckCount(self.max_deck_count),
                GeneralSetting::RequireCheckIn(self.require_check_in),
                GeneralSetting::RequireDeckReg(self.require_deck_reg),
                GeneralSetting::RoundLength(self.round_length),
            ]
            .into_iter(),
        )
    }