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: cache.go
    path of file: ./repos/client/go/kvstore
    
    the code of the file until where you have to start completion: package kvstore

import (
	"crypto/sha256"
	"encoding/hex"
	"fmt"
	"sync"

	"github.com/keybase/client/go/libkb"
	"github.com/keybase/client/go/protocol/keybase1"
)

const DeletedOrNonExistent = ""

var _ libkb.KVRevisionCacher = (*KVRevisionCache)(nil)

type kvCacheEntry struct {
	Revision   int
	EntryHash  string
	TeamKeyGen keybase1.PerTeamKeyGeneration
}

type kvCacheData map[keybase1.TeamID]map[string] /*namespace*/ map[string] /*e
    
func (k *KVRevisionCache) Put(mctx libkb.MetaContext, entryID keybase1.KVEntryID, ciphertext *string, teamKeyGen keybase1.PerTeamKeyGeneration, revision int) (err error) {
	k.Lock()
	defer k.Unlock()

	err = k.checkLocked(mctx, entryID, ciphertext, teamKeyGen, revision)
	if err != nil {
		return err
	}

	entryHash := k.hash(ciphertext)
	newEntry := kvCacheEntry{
		EntryHash:  entryHash,
		TeamKeyGen: teamKeyGen,
		Revision:   revision,
	}
	k.data[entryID.TeamID][entryID.Namespace][entryID.EntryKey] = newEntry
	return nil
}