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: client.go
    path of file: ./repos/comply/vendor/github.com/docker/docker/client
    
    the code of the file until where you have to start completion: /*
Package client is a Go client for the Docker Engine API.

For more information about the Engine API, see the documentation:
https://docs.docker.com/engine/api/

Usage

You use the library by creating a client object and calling methods on it. The
client can be created either from environment variables with NewClientWithOpts(client.FromEnv),
or configured 
    
func ParseHostURL(host string) (*url.URL, error) {
	protoAddrParts := strings.SplitN(host, "://", 2)
	if len(protoAddrParts) == 1 {
		return nil, fmt.Errorf("unable to parse docker host `%s`", host)
	}

	var basePath string
	proto, addr := protoAddrParts[0], protoAddrParts[1]
	if proto == "tcp" {
		parsed, err := url.Parse("tcp://" + addr)
		if err != nil {
			return nil, err
		}
		addr = parsed.Host
		basePath = parsed.Path
	}
	return &url.URL{
		Scheme: proto,
		Host:   addr,
		Path:   basePath,
	}, nil
}