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: sig_pnd.rs
    path of file: ./repos/procs/src/columns
    
    the code of the file until where you have to start completion: use crate::process::ProcessInfo;
use crate::{column_default, Column};
use std::cmp;
use std::collections::HashMap;

pub struct SigPnd {
    header: String,
    unit: String,
    fmt_contents: HashMap<i32, Str
    
    fn add(&mut self, proc: &ProcessInfo) {
        let (fmt_content, raw_content) = if let Some(ref status) = proc.curr_status {
            let val = status.sigpnd;
            (format!("{val:016x}"), val)
        } else {
            (String::new(), 0)
        };

        self.fmt_contents.insert(proc.pid, fmt_content);
        self.raw_contents.insert(proc.pid, raw_content);
    }