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: black.go
    path of file: ./repos/open-im-server/pkg/common/db/controller
    
    the code of the file until where you have to start completion: // Copyright Â© 2023 OpenIM. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless
    
func (b *blackDatabase) CheckIn(ctx context.Context, userID1, userID2 string) (inUser1Blacks bool, inUser2Blacks bool, err error) {
	userID1BlackIDs, err := b.cache.GetBlackIDs(ctx, userID1)
	if err != nil {
		return
	}
	userID2BlackIDs, err := b.cache.GetBlackIDs(ctx, userID2)
	if err != nil {
		return
	}
	log.ZDebug(ctx, "blackIDs", "user1BlackIDs", userID1BlackIDs, "user2BlackIDs", userID2BlackIDs)
	return utils.IsContain(userID2, userID1BlackIDs), utils.IsContain(userID1, userID2BlackIDs), nil
}