docs: def copy_object(self, container, obj, new_container, new_obj_name=None,
              content_type=None, extra_info=None):
          """
          Copies the object to the new container, optionally giving it a new name.
          If you copy to the same container, you must supply a different name.
  
          You can optionally change the content_type of the object by supplying
          that in the 'content_type' parameter.
  
          The 'extra_info' parameter is included for backwards compatibility. It
          is no longer used at all, and will not be modified with swiftclient
          info, since swiftclient is not used any more.
          """
          return self._manager.copy_object(container, obj, new_container,
                  new_obj_name=new_obj_name, content_type=content_type)