Fix error in model.go

model.go

@@ -91,8 +91,8 @@ type VoiceProcessingData struct {
 	io.ReadCloser
 
 	Client *http.Client
-	URL string
-	File string
+	URL    string
+	File   string
 
 	res *http.Response
 }
@@ -105,6 +105,8 @@ func (v *VoiceProcessingData) open() error {
 	}
 
 	v.res = res
+
+	return nil
 }
 
 func (v *VoiceProcessingData) Close() error {
@@ -148,7 +150,7 @@ func (v *VoiceProcessingData) SaveTo(file string) error {
 
 	defer v.res.Body.Close()
 
-	_, err =  io.Copy(f, v.res.Body)
+	_, err = io.Copy(f, v.res.Body)
 
 	return err
 }