code: def render_code(self):
          
          tmp_dir = os.environ.get('TMP','')
          view_code = os.path.join(tmp_dir,'view.enaml')
          if os.path.exists(view_code):
              try:
                  with open(view_code) as f:
                      return f.read()
              except:
                  pass
          return DEFAULT_CODE
docs: Try to load the previous code (if we had a crash or something)
              I should allow saving.