解组转义的XML

像这样两次解码（在操场上尝试）

package mainimport (    "encoding/xml"    "fmt")var data = `<?xml version="1.0"?><GetAssignmentResponse>    <Answer>&lt;?xml version="1.0" encoding="UTF-8" standalone="no"?&gt;        &lt;QuestionFormAnswers xmlns="http://mechanicalturk.amazonaws.com/AWSMechanicalTurkDataSchemas/2005-10-01/QuestionFormAnswers.xsd"&gt;        &lt;Answer&gt;        &lt;QuestionIdentifier&gt;Q1HasEvents&lt;/QuestionIdentifier&gt;        &lt;FreeText&gt;no&lt;/FreeText&gt;        &lt;/Answer&gt;        &lt;/QuestionFormAnswers&gt;    </Answer></GetAssignmentResponse>`type Response struct {    XMLName xml.Name `xml:"GetAssignmentResponse"`    Answer  string   `xml:"Answer"`}type Answer struct {    XMLName  xml.Name `xml:"QuestionFormAnswers"`    FreeText string   `xml:"FreeText"`}func main() {    v := Response{}    err := xml.Unmarshal([]byte(data), &v)    if err != nil {        fmt.Printf("error: %v", err)        return    }    fmt.Printf("Answer = %qn", v.Answer)    a := Answer{}    err = xml.Unmarshal([]byte(v.Answer), &a)    if err != nil {        fmt.Printf("error: %v", err)        return    }    fmt.Printf("Answer = %#vn", a)}