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: urlscan.go
    path of file: ./repos/sliver/vendor/github.com/VirusTotal/vt-go
    
    the code of the file until where you have to start completion: // Copyright Â© 2017 The vt-go authors. All Rights Reserved.
// Licensed under the Apache License, Version 2.
    
func (s *URLScanner) Scan(url string) (*Object, error) {

	b := bytes.Buffer{}
	w := multipart.NewWriter(&b)

	f, err := w.CreateFormField("url")
	if err != nil {
		return nil, err
	}

	if _, err = f.Write([]byte(url)); err != nil {
		return nil, err
	}

	w.Close()

	headers := map[string]string{"Content-Type": w.FormDataContentType()}

	httpResp, err := s.cli.sendRequest("POST", URL("urls"), &b, headers)
	if err != nil {
		return nil, err
	}
	defer httpResp.Body.Close()

	apiResp, err := s.cli.parseResponse(httpResp)
	if err != nil {
		return nil, err
	}

	analysis := &Object{}
	if err := json.Unmarshal(apiResp.Data, analysis); err != nil {
		return nil, err
	}

	return analysis, nil
}