def save(self, file):
        """ Saves the :class:`~pypot.primitive.move.Move` to a json file.

        .. note:: The format used to store the :class:`~pypot.primitive.move.Move` is extremely verbose and should be obviously optimized for long moves.
        """
        d = {
            'framerate': self.framerate,
            'positions': self._timed_positions,
        }
        json.dump(d, file, indent=2)