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: client.go
    path of file: ./repos/Distributed-Systems/6.824/src/diskv
    
    the code of the file until where you have to start completion: package diskv

import "shardmaster"
import "net/rpc"
import "time"
import "sync"
import "fmt"
import "crypto/rand"
import "math/big"

type Clerk struct {
	mu     sync.Mutex // one RPC at a time
	sm     *shardmaster.Clerk
	config shardmaster.Config
	// You'll have to modify Clerk.
}

fun
    
func (ck *Clerk) Get(key string) string {
	ck.mu.Lock()
	defer ck.mu.Unlock()

	// You'll have to modify Get().

	for {
		shard := key2shard(key)

		gid := ck.config.Shards[shard]

		servers, ok := ck.config.Groups[gid]

		if ok {
			// try each server in the shard's replication group.
			for _, srv := range servers {
				args := &GetArgs{}
				args.Key = key
				var reply GetReply
				ok := call(srv, "DisKV.Get", args, &reply)
				if ok && (reply.Err == OK || reply.Err == ErrNoKey) {
					return reply.Value
				}
				if ok && (reply.Err == ErrWrongGroup) {
					break
				}
			}
		}

		time.Sleep(100 * time.Millisecond)

		// ask master for a new configuration.
		ck.config = ck.sm.Query(-1)
	}
}