code: def wrap_content(cls, container, wrapper):
          "wrap the content of container element with wrapper element"
          wrapper.text = (container.text or '') + (wrapper.text or '')
          container.text = ''
          for ch in container:
              wrapper.append(ch)
          container.insert(0, wrapper)
          return containef wrap_content(cls, container, wrapper):
          "wrap the content of container element with wrapper element"
          wrapper.text = (container.text or '') + (wrapper.text or '')
          container.text = ''
          for ch in container:
              wrapper.append(ch)
          container.insert(0, wrapper)
          return container
docs: wrap the content of container element with wrapper element