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: build.rs
    path of file: ./repos/kcl/kclvm/api
    
    the code of the file until where you have to start completion: use std::{env, path::PathBuf};

use prost_wkt_build::{FileDescriptorSet, Message};

/// According to the file kclvm/spec/gpyrpc/gpyrpc.proto, automatically generate
/// the corresponding rust source file to the directory src/model
fn main() {
    std::env::set_var(
        "PROTOC",
        protoc_bin_vendored::protoc_bin_path().unwrap().as_os_str(),
    );

    let out = PathBuf::from(env::var("OUT_DIR").unwrap());
    let descriptor_file = out.join("kclvm_service_descriptor.bin");

    let mut prost_build = prost_build::Config::new();
    prost_build
        .type_attribute(".", "#[derive(serde::Serialize,serde::Deserialize)]")
        .field_attribute(".", "#[serde(default)]")
        .extern_path(".google.protobuf.Any", "::prost_wkt_types::Any")
        .extern_path(".google.protobuf.Timestamp", "::prost
    
fn main() {
    std::env::set_var(
        "PROTOC",
        protoc_bin_vendored::protoc_bin_path().unwrap().as_os_str(),
    );

    let out = PathBuf::from(env::var("OUT_DIR").unwrap());
    let descriptor_file = out.join("kclvm_service_descriptor.bin");

    let mut prost_build = prost_build::Config::new();
    prost_build
        .type_attribute(".", "#[derive(serde::Serialize,serde::Deserialize)]")
        .field_attribute(".", "#[serde(default)]")
        .extern_path(".google.protobuf.Any", "::prost_wkt_types::Any")
        .extern_path(".google.protobuf.Timestamp", "::prost_wkt_types::Timestamp")
        .extern_path(".google.protobuf.Value", "::prost_wkt_types::Value")
        .file_descriptor_set_path(&descriptor_file)
        .compile_protos(&["../spec/gpyrpc/gpyrpc.proto"], &["../spec/gpyrpc/"])
        .expect("Running prost build failed.");

    let descriptor_bytes = std::fs::read(descriptor_file).unwrap();

    let descriptor = FileDescriptorSet::decode(&descriptor_bytes[..]).unwrap();

    prost_wkt_build::add_serde(out, descriptor);
}