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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def apply_vnc_actions(self, vnc_actions):
 """ Play a list of vnc_actions forward over the current keysyms state NOTE: Since we are squashing a set of diffs into a single keyboard state, some information may be lost. For example if the Z key is down, then we receive [(Z-up), (Z-down)], the output will not reflect any change in Z You can make each frame shorter to offset this effect. """

        for event in vnc_actions:
            if isinstance(event, spaces.KeyEvent):
                if event.down:
                    self._down_keysyms.add(event.key)
                else:
                    self._down_keysyms.discard(event.key)

        logger.debug("AtariKeyState._down_keysyms: {}".format(self._down_keysyms))