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: mod.rs
    path of file: ./repos/Siffra/core/src/representations/dimension
    
    the code of the file until where you have to start completion: mod amount;
mod angle;
mod chemical;
mod length;
mod macros;
mod mass;
mod temperature;
mod time;

use crate::representations::Float;
use std::collections::BTreeMap;
use std::fmt::Display;
use std::ops::Neg;
use std::str::FromStr;

pub use {
    amount::Amount,
    angle::Angle,
    chemical::{Compound, Element},
    length::Length,
    mass::Mass,
    temperature::Temperatur
    
    pub fn shorthand(&self) -> String {
        match self {
            Quantity::Length(length) => length.shorthand().to_string(),
            Quantity::Time(time) => time.shorthand().to_string(),
            Quantity::Mass(mass, compound) => {
                if let Some(compound) = compound {
                    mass.shorthand().to_string() + " " + &*compound.to_string()
                } else {
                    mass.shorthand().to_string()
                }
            }
            Quantity::Amount(amount, compound) => {
                if let Some(compound) = compound {
                    amount.shorthand().to_string() + " " + &*compound.to_string()
                } else {
                    amount.shorthand().to_string()
                }
            }
            Quantity::Angle(angle) => angle.shorthand().to_string(),
            Quantity::TemperatureInterval(temperature) => temperature.shorthand().to_string(),
        }
    }