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: parse.go
    path of file: ./repos/zeebe/clients/go/vendor/github.com/docker/docker/api/types/filters
    
    the code of the file until where you have to start completion: /*
Package filters provides tools for encoding a mapping of keys to a set of
multiple values.
*/
package filters // import "github.com/docker/docker/api/types/filters"

import (
	"encoding/json"
	"regexp
    
func (args Args) WalkValues(field string, op func(value string) error) error {
	if _, ok := args.fields[field]; !ok {
		return nil
	}
	for v := range args.fields[field] {
		if err := op(v); err != nil {
			return err
		}
	}
	return nil
}