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: cast.go
    path of file: ./repos/werf/pkg/util
    
    the code of the file until where you have to start completion: package util

import "fmt"

func MapStringInterfaceToMapStringString(value map[string]interface{}) map[string]string {
	result := map[string]string{}
	for key, valueInterf := range value {
		result[key] = fmt.Sprintf("%v", valueInterf)
	}

	return res
    
func InterfaceArrayToStringArray(array []interface{}) ([]string, error) {
	var result []string
	for _, value := range array {
		if str, ok := value.(string); !ok {
			return nil, fmt.Errorf("value `%#v` can't be casted into string", value)
		} else {
			result = append(result, str)
		}
	}
	return result, nil
}