def change_object_content_type(self, container, obj, new_ctype,
            guess=False, extra_info=None):
        """
        Copies object to itself, but applies a new content-type. The guess
        feature requires the container to be CDN-enabled. If not then the
        content-type must be supplied. If using guess with a CDN-enabled
        container, new_ctype can be set to None. Failure during the put will
        result in a swift exception.

        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.change_object_content_type(container, obj,
                new_ctype, guess=guess)
Copies object to itself, but applies a new content-type. The guess
        feature requires the container to be CDN-enabled. If not then the
        content-type must be supplied. If using guess with a CDN-enabled
        container, new_ctype can be set to None. Failure during the put will
        result in a swift exception.

        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.