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: chunk.rs
    path of file: ./repos/occlum/src/libos/src/vm
    
    the code of the file until where you have to start completion: use super::*;

use super::vm_area::VMArea;
use super::vm_chunk_manager::ChunkManager;
use super::vm_perms::VMPerms;
use super::vm_util::*;
use crate::process::ProcessRef;
use crate::process::ThreadRef;

use std::cmp::Ordering;
use std::collections::HashSet;
use std::hash::{Hash, Has
    
    pub fn clean_multi_vmas(&mut self) -> bool {
        let current_pid = current!().process().pid();
        self.chunk_manager.clean_vmas_with_pid(current_pid);
        if self.chunk_manager.is_empty() {
            self.process_set.remove(&current_pid);
            return true;
        } else {
            return false;
        }
    }