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/engine/src/cloud_provider/self_managed/chart_gen
    
    the code of the file until where you have to start completion: use derive_more::Display;
use semver::Version;
use std::path::Path;
use url::Url;

use crate::cloud_provider::kubernetes::KubernetesVersion;

use self::chart_dot_yaml::{ChartDotYamlApiVersion, ChartDotYamlType};
use self::values_dot_yaml::ChartCategory;

pub mod chart_dot_yaml;
pub mod io;
pub mod values_d
    
    pub fn copy_recursively(source: impl AsRef<Path>, destination: impl AsRef<Path>) -> io::Result<()> {
        fs::create_dir_all(&destination)?;
        for entry in fs::read_dir(source)? {
            let entry = entry?;
            let filetype = entry.file_type()?;
            if filetype.is_dir() {
                copy_recursively(entry.path(), destination.as_ref().join(entry.file_name()))?;
            } else {
                fs::copy(entry.path(), destination.as_ref().join(entry.file_name()))?;
            }
        }
        Ok(())
    }