code: func Request(entity HttpRequestEntity, method string, body io.Reader) (response *http.Response, err error) {
  	transport := NewRoundTripper()
  	req, err := http.NewRequest(method, entity.Url, body)
  	if err != nil {
  		return
  	}
  
  	if entity.Authorization == "" {
  		req.SetBasicAuth(entity.Username, entity.Password)
  
  	} else {
  		req.Header.Add("Authorization", entity.Authorization)
  	}
  
  	if entity.ContentType != NO_CONTENT_TYPE {
  		req.Header.Add("Content-Type", entity.ContentType)
  	}
  	return transport.RoundTrip(req)
  }
docs: //Request -