    def sync(self):
        """
        Synchronize the screen buffer with the double buffer.
        """
        # We're copying an array of tuples, so only need to copy the 2-D array (as the tuples are immutable).
        # This is way faster than a deep copy (which is INCREDIBLY slow).
        self._screen_buffer = [row[:] for row in self._double_buffer]
Synchronize the screen buffer with the double buffer.
asciimatics/screen.py