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: file_store.go
    path of file: ./repos/kubeedge/vendor/github.com/docker/cli/cli/config/credentials
    
    the code of the file until where you have to start completion: package credentials

import (
	"strings"

	"github.com/docker/cli/cli/config/types"
)

type store interface {
	Save() error
	GetAuthConfigs() map[string]types.AuthConfig
	GetFilename() string
}

// fileStore implements a 
    
func (c *fileStore) Get(serverAddress string) (types.AuthConfig, error) {
	authConfig, ok := c.file.GetAuthConfigs()[serverAddress]
	if !ok {
		// Maybe they have a legacy config file, we will iterate the keys converting
		// them to the new format and testing
		for r, ac := range c.file.GetAuthConfigs() {
			if serverAddress == ConvertToHostname(r) {
				return ac, nil
			}
		}

		authConfig = types.AuthConfig{}
	}
	return authConfig, nil
}