Change a sprite from url

Basicly I'm trying to change a player picture based on his picture online. I've found a way to create sprites and change that picture (http://answers.unity3d.com/questions/581524/creating-sprite-in-code-using-textureimporter-with.html) but what I want its to change a current sprite and I'm not being able to adapt that code.

This is what I've tried:

 IEnumerator User1()
     {
         //can be used to load textures from url OR from local computer/device
         WWW www = new WWW(url);
         yield return www; 
         
         Sprite sprite = new Sprite();
         sprite = Sprite.Create(www.texture,new Rect(0, 0, 170, 170),new Vector2(0, 0),100.0f);
         user1.gameObject.GetComponent<SpriteRenderer>().sprite = sprite;
 
     }